POJ-2459

#include<iostream>#include<memory.h>using namespace std;#define MAX_DAY 2000int main(int argc, char *argv[]){int array[MAX_DAY+1];memset(array,0,(MAX_DAY+1)*sizeof(int));int c, f1, f2, d;cin>>c>>f1>>f2>>d;for(int i=0;i<c;i++){int dArrive, dLeave;cin>>dArrive>>dLeave;for(int j=dArrive;j<=dLeave;j++){array[j]++;}}for(int m=d;;m--){f1-=array[m];if(f1==f2){cout<<m<<endl;break;}}return 0;}