poj2431 Expedition

直接代码、、、

#include<string.h>
#include<stdio.h>
#include<queue>
#include<iostream>
#include<algorithm>
using namespace std;
struct node
{int fuel,dist;//bool operator < (const node&d) const{// return  dist>d.dist;// }
}s[10005];
bool cmp(node b,node c)
{return b.dist>c.dist;
}
int main()
{int a,l,p,pos,ans,d,fuels;scanf("%d",&a);priority_queue<int> q;for(int i=0;i<a;i++){scanf("%d %d\n",&s[i].dist,&s[i].fuel);}sort(s,s+a,cmp);//从大到小进行排序，scanf("%d %d",&l,&p);s[a].dist=0;for(int i=0;i<=a;i++)s[i].dist=l-s[i].dist;fuels=p;ans=0;pos=0;for(int i=0;i<=a;i++){d=s[i].dist-pos;while(fuels-d<0){if(q.empty()){printf("-1\n");return 0;}fuels+=q.top();q.pop();ans++;}fuels-=d;pos=s[i].dist;q.push(s[i].fuel);}printf("%d\n",ans);return 0;
}