这道题跟hdoj4882 ZCC Loves Codefires 几乎一模一样,只是改了一下下。
解题策略 :参考hdoj4882的解法 http://blog.youkuaiyun.com/shengweisong/article/details/38316699
题目链接 http://poj.org/problem?id=3262
代码:
#include<stdio.h>
#include<string.h>
#include<algorithm>
using namespace std;
typedef struct{
double t, d;
double r;
}str;
str s[100005];
int cmp(str a, str b)
{
return a.r<b.r;
}
int main()
{
int n, i, j;
while(scanf("%d", &n) == 1){
for(i = 0; i < n; i ++){
scanf("%lf%lf", &s[i].t, &s[i].d);
s[i].r = s[i].t/s[i].d;
}
sort(s, s+n, cmp);
__int64 sum =0, time = 2*s[0].t; //和hdoj4882 这处有点小小的改变
for(i = 1; i < n; i ++){
sum += time *s[i].d;
time += 2*s[i].t;
}
printf("%I64d\n", sum);
}
}