注意 保留位数是在格式前，例如 printf("%.2f",s);
#include<stdio.h> #include<algorithm> using namespace std; const int maxn =50000; struct mooncake { double score; double sell; double price; }cake[maxn]; bool cmp(mooncake a,mooncake b) { return a.price>b.price; } int main() { int n;//月饼种类 int D;//总需求量; for(int i=0;i<n;i++) { scanf("%d",& cake[i].score); } for(int i=0;i<n;i++) { scanf("%d",&cake[i].sell); cake[i].price=cake[i].sell/cake[i].score; } sort(cake,cake+n,cmp);//sort函数将月饼按单价排序 double ans=0; for(int i=0;i<n;i++) { if(cake[i].score<D) { ans+=cake[i].sell; } else { ans=(D-cake[i].score)*cake[i].price; printf("%.2f\n",ans); } } }