HDU Wooden Sticks (Greedy)

HDU Wooden Sticks (Greedy)
Wooden SticksTime Limit: 2000/1000 ms (Java/Other) Memory Limit: 65536/32768 K (Java/Other) Total Submission (s): 19 Accepted Submission (s): 7 Font: times New Roman | Verdana | GeorgiaFont Size: Batch → Problem DescriptionThere is a pile of n wooden sticks. the length and weight of each stick are known in advance. the sticks are to be processed by a woodworking machine in one by one fashion. it needs some time, called setup time, for the machine to prepare processing a stick. the setup times are associated with cleaning operations and changing tools and shapes in the machine. the setup times of the woodworking machine are given as follows:

(A) The setup time for the first wooden stick is 1 minute.
(B) Right after processing a stick of length l and weight w, the machine will need no setup time for a stick of length l' and weight W' if l <= l' and w <= W '. otherwise, it will need 1 minute for setup.

You are to find the minimum setup time to process a given pile of n wooden sticks. for example, if you have five sticks whose pairs of length and weight are (), and ), then the minimum setup time shocould be 2 minutes since there is a sequence of pairs ).
InputThe input consists of T test cases. the number of test cases (T) is given in the first line of the input file. each test case consists of two lines: The first line has an integer n, 1 <= n <= 5000, that represents the number of wooden sticks in the test case, and the second line contains n 2 positive integers l1, w1, l2, w2 ,..., ln, wn, each of magnloud at most 10000, where li and wi are the length and weight of the I th wooden stick, respectively. the 2n integers are delimited by one or more spaces.
OutputThe output shoshould contain the minimum setup time in minutes, one per line.
Sample Input

3 5 4 9 5 2 2 1 3 5 1 4 3 2 2 1 1 2 2 3 1 3 2 2 3 1

Sample Output

213

SourceAsia 2001, Taejon (South Korea) AC code:

#include 
 
  #include #include 
  
   #include 
   
    using namespace std;struct wooden{    int l,w;};wooden my[5010];bool comp(wooden a,wooden b){    if(a.l>b.l)return 1;    else if(a.l==b.l)        return a.w>b.w;    else return 0;}int main(){    int t;    cin>>t;    while(t--){        int n;        cin>>n;        int i=0,j;        while(i
    
     >my[i++].l>>my[i].w;        sort(my,my+n,comp);        //for(i=0;i
     
      =my[i].l&&my[j].w>=my[i].w){            out--;            my[j].l=my[i].l;            my[j].w=my[i].w;            my[i].l=0;            my[i].w=0;            break;            }        }        // for(i=0;i