POJ 3190 Stall Reservations (greedy)

Stall Reservations

Time Limit: 1000MS		Memory Limit: 65536K
Total Submissions: 3590		Accepted: 1284		Special Judge

Description

Oh those picky n (1 <= n <= 50,000) cows! They is so picky, each one is only being milked over some precise time interval A. B (1 <= a <= b <= 1,000,000), which includes both times A and B. Obviously, FJ must create A reservation system t o determine which stall each cow can is assigned for her milking time. Of course, no cow would share such a private moment with other cows.

Help FJ by determining:

• The minimum number of stalls required in the barn so, each cow can has her private milking period
• An assignment of cows to these stalls over time

Many answers is correct for each test dataset; A program would grade your answer.

Input

Line 1: A single integer, N

Lines 2..n+1:line i+1 describes cow i ' s milking interval with the space-separated integers.

Output

Line 1:the minimum number of stalls the barn must has.

Lines 2..n+1:line i+1 describes the stall to which cow I'll be a assigned for her milking period.

Sample Input

51 102 43 65 84 7

Sample Output

412324

Hint

Explanation of the sample:

Here's a graphical schedule for this output:

Time     1  2  3  4  5  6  7  8  9 10Stall 1 c1>>>>>>>>>> >>>>>>>>>>>>>>>>>stall 2.. C2>>>>>> c4>>>>>>>>>. .. Stall 3.. .. C3>>>>>>>>>. .. .. .. Stall 4.. .. .. C5>>>>>>>>>. .. ..

Other outputs using the same number of stalls is possible.

Source

Usaco 2006 February Silver

#include <iostream> #include <cstdio> #include <cstring> #include <algorithm> #include < cmath> #include <queue> #include <stack> #include <vector> #include <set> #include <map > #define L (x) (x<<1) #define R (x) (x<<1|1) #define MID (x, y) ((x+y) >>1) #define EPST 1e-8typedef __ Int64 ll; #define FRE (i,a,b) for (i = A; I <b; i++) #define FREE (i,b,a) for (i = b; I >= a;i--) #define MEM (T, v) MEMS ET ((t), V, sizeof (t)) #define SSF (n) scanf ("%s", N) #define SF (n) scanf ("%d", &n) #define SFF (A, b) scanf (          "%d%d", &a, &b) #define SFFF (a,b,c) scanf ("%d%d%d", &a, &b, &c) #define PF Printf#define Bug  PF ("hi\n") using namespace std, #define INF 0x3f3f3f3f#define n 50005struct stud{int x, y;  int POS;  BOOL operator < (CONST stud D) Const {return y>d.y; }}f[n];int ans[n];int k;priority_queue<stud>q;int n;int cmp (stud A,stud b) {if (a.x==b.x) return A.y<b.y;return a.x<b.x;} voidSolve () {int I,j;stud cur;while (!q.empty ()) Q.pop (); for (i=1;i<=n;i++) {if (Q.empty ()) {Ans[f[i].pos]=++k;q.push (f[        I]); continue;}        Cur=q.top ();        if (cur.y<f[i].x) {Ans[f[i].pos]=ans[cur.pos];q.pop ();}        else ans[f[i].pos]=++k; Q.push (F[i]);}}    int main () {int i,j;while (~SF (n)) {for (i=1;i<=n;i++) {SFF (F[I].X,F[I].Y); F[i].pos=i;}    Sort (f+1,f+n+1,cmp); K=0;solve ();p F ("%d\n", K), for (i=1;i<=n;i++) pf ("%d\n", Ans[i]);} return 0;}

POJ 3190 Stall Reservations (greedy)