Codeforces Round #303 (Div. 2)

Source: Internet
Author: User
Tags cmath

Codeforces Round #303 (Div. 2)

 

One question + four greedy ones ....

 

 

Codeforces Round #303 (Div. 2) A. Toy Cars time limit per test 1 second memory limit per test 256 megabytes input standard input output standard output

Little Susie, thanks to her older brother, likes to play with cars. Today she decided to set up a tournament between them. The process of a tournament is described in the next paragraph.

There areNToy cars. each pair collides. the result of a collision can be one of the following: no car turned over, one car turned over, both cars turned over. A car is good if it turned over in no collision. the results of the collisions are determined byN? ×?NMatrixBytes: There is a number on the intersection of?-Th row andJ-Th column that describes the result of the collision of?-Th andJ-Th car:

  • ? -? 1: if this pair of cars never collided .? -? 1 occurs only on the main diagonal of the matrix.
  • 0: if no car turned over during the collision.
  • 1: if onlyI-Th car turned over during the collision.
  • 2: if onlyJ-Th car turned over during the collision.
  • 3: if both cars turned over during the collision.

    Susie wants to find all the good cars. She quickly determined which cars are good. Can you compare with the task?

    Input

    The first line contains integerN(1? ≤?N? ≤? 100)-the number of cars.

    Each of the nextNLines containsNSpace-separated integers that determine matrixA.

    It is guaranteed that on the main diagonal there are? -? 1, and? -? 1 doesn' t appear anywhere else in the matrix.

    It is guaranteed that the input is correct, that is, ifAIj? =? 1, thenAJi? =? 2, ifAIj? =? 3, thenAJi? =? 3, and ifAIj? =? 0, thenAJi? =? 0.

    Output

    Print the number of good cars and in the next line print their space-separated indices in the increasing order.

    Sample test (s) input
    3-1 0 00 -1 10 2 -1
    Output
    21 3 
    Input
    4-1 3 3 33 -1 3 33 3 -1 33 3 3 -1
    Output
    0
    /*************************************** * ******** Author: CKbossCreated Time: Wednesday, June 16, May 20, 2015 File Name:. cpp *************************************** * *********/# include
       
        
    # Include
        
         
    # Include
         
          
    # Include
          
           
    # Include
           
            
    # Include
            
              # Include
             
               # Include
              
                # Include
               
                 # Include
                Using namespace std; const int maxn = 111; int n; int mat [maxn] [maxn]; vector
                 
                   Vi; int main () {// freopen ("in.txt", "r", stdin); // freopen ("out.txt", "w", stdout ); scanf ("% d", & n); for (int I = 1; I <= n; I ++) {bool flag = true; for (int j = 1; j <= n; j ++) {scanf ("% d", & mat [I] [j]); if (mat [I] [j] = 1 | mat [I] [j] = 3) flag = false;} if (flag) vi. push_back (I);} int sz = vi. size (); printf ("% d \ n", sz); for (int I = 0; I
                  
                    B. Equidistant Stringtime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard output
                   

    Little Susie loves strings. Today she calculates distances between them. As Susie is a small girl after all, her strings contain only digits zero and one. She uses the definition of Hamming distance:

    We will define the distance between two stringsSAndTOf the same length consisting of digits zero and one as the number of positionsI, Such thatSIIsn' t equalTI.

    As besides everything else Susie loves ry, she wants to find for two stringsSAndTOf lengthNSuch stringPOf lengthN, That the distance fromPToSWas equal to the distance fromPToT.

    It's time for Susie to go to bed, help her find such stringPOr state that it is impossible.

    Input

    The first line contains stringSOf lengthN.

    The second line contains stringTOf lengthN.

    The length of stringNIs within range from 1 to 105. It is guaranteed that both strings contain only digits zero and one.

    Output

    Print a string of lengthN, Consisting of digits zero and one, that meets the problem statement. If no such string exist, print on a single line "impossible" (without the quotes ).

    If there are multiple possible answers, print any of them.

    Sample test (s) input
    00011011
    Output
    0011
    Input
    000111
    Output
    impossible
    Note

    In the first sample different answers are possible, namely-0010,001 1, 0110,011 1, 1000,100 1, 1100,110 1.

    Situation analysis:
    /*************************************** * ******** Author: CKbossCreated Time: Wednesday, January 1, May 20, 2015 File Name: B. cpp *************************************** * *********/# include
                    
                     
    # Include
                     
                      
    # Include
                      
                       
    # Include
                       
                        
    # Include
                        
                         
    # Include
                         
                           # Include
                          
                            # Include
                           
                             # Include
                            
                              # Include
                             Using namespace std; const int maxn = 1001000; int n; char s [maxn]; char t [maxn]; char p [maxn]; int main () {// freopen ("in.txt", "r", stdin); // freopen ("out.txt", "w", stdout); scanf ("% s ", s); scanf ("% s", t); int n = strlen (s); int diff01 = 0, diff10 = 0; for (int I = 0; I
                              
                                C. Woodcutterstime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard output
                               

    Little Susie listens to fairy tales before bed every day. today's fairy tale was about wood cutters and the little girl immediately started imagining the choppers cutting wood. she imagined the situation that is described below.

    There areNTrees located along the road at points with coordinatesX1 ,?X2 ,?...,?XN. Each tree has its heightHI. Woodcutters can cut down a tree and fell it to the left or to the right. After that it occupies one of the segments [XI? -?HI,?XI] Or [XI;XI? +?HI]. The tree that is not cut down occupies a single point with coordinateXI. Woodcutters can fell a tree if the segment to be occupied by the fallen tree doesn't contain any occupied point. the woodcutters want to process as your trees as possible, so Susie wonders, what is the maximum number of trees to fell.

    Input

    The first line contains integerN(1? ≤?N? ≤? 105)-the number of trees.

    NextNLines contain pairs of integersXI,?HI(1? ≤?XI,?HI? ≤? (109)-the coordinate and the height of?-Th tree.

    The pairs are given in the order of ascendingXI. No two trees are located at the point with the same coordinate.

    Output

    Print a single number-the maximum number of trees that you can cut down by the given rules.

    Sample test (s) input
    51 22 15 1010 919 1
    Output
    3
    Input
    51 22 15 1010 920 1
    Output
    4
    Note

    In the first sample you can fell the trees like that:

    • Fell the 1-st tree to the left-now it occupies segment [? -? 1; 1]
    • Fell the 2-nd tree to the right-now it occupies segment [2; 3]
    • Leave the 3-rd tree-it occupies point 5
    • Leave the 4-th tree-it occupies point 10
    • Fell the 5-th tree to the right-now it occupies segment [19; 20]

      In the second sample you can also fell 4-th tree to the right, after that it will occupy segment [10; 19].

      Greedy, try to reverse to the left, if not to the right (it will not affect the optimal value)

       

      /*************************************** * ******** Author: CKbossCreated Time: July 22, Wednesday, File Name: C. cpp *************************************** * *********/# include
                                    
                                     
      # Include
                                     
                                      
      # Include
                                      
                                       
      # Include
                                       
                                        
      # Include
                                        
                                         
      # Include
                                         
                                           # Include
                                          
                                            # Include
                                           
                                             # Include
                                            
                                              # Include
                                             Using namespace std; const int maxn = 100100; int n; struct Tree {int x, h;} tree [maxn]; bool cmp (Tree a, Tree B) {if (. x! = B. x) return a. x
                                              
                                               

       

      D. Queuetime limit per test1 secondmemory limit per test256 megabytesinputstandard inputoutputstandard output

      Little girl Susie went shopping with her mom and she wondered how to improve service quality.

      There areNPeople in the queue. For each person we know timeTINeeded to serve him. A person will be disappointed if the time he waits is more than the time needed to serve him. the time a person waits is the total time when all the people who stand in the queue in front of him are served. susie thought that if we swap some people in the queue, then we can decrease the number of people who are disappointed.

      Help Susie find out what is the maximum number of not disappointed people can be achieved by swapping people in the queue.

      Input

      The first line contains integerN(1? ≤?N? ≤? 105 ).

      The next line containsNIntegersTI(1? ≤?TI? ≤? 109), separated by spaces.

      Output

      Print a single number-the maximum number of not disappointed people in the queue.

      Sample test (s) input
      515 2 1 5 3
      Output
      4
      Note

      Value 4 is achieved at such an arrangement, for example: 1 ,? 2 ,? 3 ,? 5 ,? 15. Thus, you can make everything feel not disappointed before t for the person with time 5.

       

      Greedy: Sorting from small to large. skip this step if angry already exists.

       

      /*************************************** * ******** Author: CKbossCreated Time: Wednesday, June 17, May 20, 2015 File Name: D. cpp *************************************** * *********/# include
                                                
                                                 
      # Include
                                                 
                                                  
      # Include
                                                  
                                                   
      # Include
                                                   
                                                    
      # Include
                                                    
                                                     
      # Include
                                                     
                                                       # Include
                                                      
                                                        # Include
                                                       
                                                         # Include
                                                        
                                                          # Include
                                                         Using namespace std; typedef long int LL; int n; LL t [100100]; int main () {// freopen ("in.txt", "r", stdin ); // freopen ("out.txt", "w", stdout); scanf ("% d", & n); for (int I = 0; I
                                                          
                                                            > T [I]; sort (t, t + n); LL total = 0; int allright = 0; for (int I = 0; I
                                                           
                                                             = T [I]) {continue;} int angry = 0; total = 0; for (int I = 0; I
                                                            
                                                              T [I]) angry ++; else total + = t [I];} printf ("% d \ n", max (allright, n-angry )); return 0 ;}
                                                            
                                                           
                                                          
                                                        
                                                       
                                                      
                                                     
                                                    
                                                   
                                                  
                                                 
                                                


       

      E. Paths and Trees time limit per test 3 seconds memory limit per test 256 megabytes input standard input output standard output

      Little girl Susie accidentally found her elder brother's notebook. she has implements things to do, more important than solving problems, but she found this problem too interesting, so she wanted to know its solution and decided to ask you about it. so, the problem statement is as follows.

      Let's assume that we are given a connected weighted undirected graphG? =? (V,?E) (HereVIs the set of vertices,EIs the set of edges). The shortest-path tree from vertexUIs such graphG1? =? (V,?E1) that is a tree with the set of edgesE1 that is the subset of the set of edges of the initial graphE, And the lengths of the shortest paths fromUTo any vertexGAndG1 are the same.

      You are given a connected weighted undirected graphGAnd vertexU. Your task is to find the shortest-path tree of the given graph from vertexU, The total weight of whose edges is minimum possible.

      Input

      The first line contains two numbers,NAndM(1? ≤?N? ≤? 3 · 105, 0? ≤?M? ≤? 3. 105)-the number of vertices and edges of the graph, respectively.

      NextMLines contain three integers each, representing an edge-UI,?VI,?WI-The numbers of vertices connected by an edge and the weight of the edge (UI? ?VI,? 1? ≤?WI? ≤? 109). It is guaranteed that graph is connected and that there is no more than one edge between any pair of vertices.

      The last line of the input contains integerU(1? ≤?U? ≤?N)-The number of the start vertex.

      Output

      In the first line print the minimum total weight of the edges of the tree.

      In the next line print the indices of the edges that are stored in the tree, separated by spaces. the edges are numbered starting from 1 in the order they follow in the input. you may print the numbers of the edges in any order.

      If there are multiple answers, print any of them.

      Sample test (s) input
      3 31 2 12 3 11 3 23
      Output
      21 2 
      Input
      4 41 2 12 3 13 4 14 1 24
      Output
      42 3 4 
      Note

      In the first sample there are two possible shortest path trees:

      • With edges 1? -? 3 and 2? -? 3 (the total weight is 3 );
      • With edges 1? -? 2 and 2? -? 3 (the total weight is 2 );

        And, for example, a tree with edges 1? -? 2 and 1? -? 3 won't be a shortest path tree for vertex 3, because the distance from vertex 3 to vertex 2 in this tree equals 3, and in the original graph it is 1.

         

         

        Greedy: Add as small an edge as possible when Dijkstra adds an edge

         

         

        /*************************************** * ******** Author: CKbossCreated Time: Wednesday, June 16, May 20, 2015 File Name: e2.cpp *************************************** * *********/# include
                                                    
                                                     
        # Include
                                                     
                                                      
        # Include
                                                      
                                                       
        # Include
                                                       
                                                        
        # Include
                                                        
                                                         
        # Include
                                                         
                                                           # Include
                                                          
                                                            # Include
                                                           
                                                             # Include
                                                            
                                                              # Include
                                                             Using namespace std; typedef long int LL; typedef pair
                                                              
                                                                PII; const LL maxn = 300300; const ll inf = 0x3f3f3f3f3f3f3f; LL n, m, S; struct Edge {LL to, next, len, id ;} edge [maxn * 2]; LL Adj [maxn], Size; void init () {memset (Adj,-1, sizeof (Adj); Size = 0 ;} void Add_Edge (LL u, LL v, LL len, LL id) {edge [Size]. to = v; edge [Size]. len = len; edge [Size]. id = id; edge [Size]. next = Adj [u]; Adj [u] = Size ++;} LL dist [maxn]; bool vis [maxn]; LL ex [maxn]; LL pre [maxn]; void dijkstra () {memset (dist, 63, sizeof (dist); memset (ex, 63, sizeof (ex )); dist [S] = 0; ex [S] = 0; priority_queue
                                                               
                                                                 Q; //-distance, click q. push (make_pair (0, S); while (! Q. empty () {pII tp = q. top (); q. pop (); LL u = tp. second; if (vis [u] = true) continue; vis [u] = true; for (LL I = Adj [u]; ~ I; I = edge [I]. next) {LL v = edge [I]. to; LL len = edge [I]. len; LL id = edge [I]. id; if (vis [v]) continue; if (dist [v]> dist [u] + len) {dist [v] = dist [u] + len; pre [v] = id; ex [v] = len; q. push (make_pair (-dist [v], v);} else if (dist [v] = dist [u] + len & ex [v]> len) {pre [v] = id; ex [v] = len ;}} LL all = 0; memset (vis, 0, sizeof (vis); vector
                                                                
                                                                  Ve; for (LL I = 1; I <= n; I ++) {if (ex [I]! = INF) all + = ex [I]; if (I! = S) ve. push_back (pre [I]);} printf ("% I64d \ n", all); sort (ve. begin (), ve. end (); unique (ve. begin (), ve. end (); for (int I = 0, sz = ve. size (); I
                                                                 
                                                                  

         

         

         

         

Contact Us

The content source of this page is from Internet, which doesn't represent Alibaba Cloud's opinion; products and services mentioned on that page don't have any relationship with Alibaba Cloud. If the content of the page makes you feel confusing, please write us an email, we will handle the problem within 5 days after receiving your email.

If you find any instances of plagiarism from the community, please send an email to: info-contact@alibabacloud.com and provide relevant evidence. A staff member will contact you within 5 working days.

A Free Trial That Lets You Build Big!

Start building with 50+ products and up to 12 months usage for Elastic Compute Service

  • Sales Support

    1 on 1 presale consultation

  • After-Sales Support

    24/7 Technical Support 6 Free Tickets per Quarter Faster Response

  • Alibaba Cloud offers highly flexible support services tailored to meet your exact needs.