标签:space instead begin ase lines stream work node ready
5 3 7 2 4 3 5 2 20 3 25 18 24 15 15 10 -1 -1
13.333 31.500
【题意】一只老鼠有n的猫粮,一只猫有m间房,每间房有num的豆需要val的猫粮换取,求最大能换到的豆
【思路】简单的贪心问题
#include<iostream> #include<stdio.h> #include<string.h> #include<algorithm> using namespace std; const int N=1000+10; int n,m; struct node { double num; double val; double p; }a[N]; bool cmp(node a,node b) { return a.p>b.p; } int main() { while(scanf("%d%d",&n,&m)!=EOF) { if(m==-1&&n==-1) break; for(int i=1;i<=m;i++) { scanf("%lf%lf",&a[i].num,&a[i].val); a[i].p=1.0*a[i].num/a[i].val; } sort(a+1,a+m+1,cmp); double ans=0; for(int i=1;i<=m;i++) { if(n==0) break; if(a[i].val<=n) { n-=a[i].val; ans+=a[i].num; } else { ans+=1.0*n*a[i].p; break; } } printf("%.3lf\n",ans); } return 0; }
标签:space instead begin ase lines stream work node ready
原文地址:http://www.cnblogs.com/iwantstrong/p/6049294.html