poj 3262 比例贪心

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题意：

给时间，给消耗数。

每次带走一头牛，求最小花费。

解析：

亮GG刚开始讲贪心时候的那个英雄联盟比例贪心。

代码：

#include <iostream>#include <cstdio>#include <cstdlib>#include <algorithm>#include <cstring>#include <cmath>#include <stack>#include <vector>#include <queue>#include <map>#include <climits>#include <cassert>#define LL long long#define lson lo, mi, rt << 1#define rson mi + 1, hi, rt << 1 | 1using namespace std;const int maxn = 1e5 + 10;const int inf = 0x3f3f3f3f;const double eps = 1e-8;const double pi = acos(-1.0);const double ee = exp(1.0);struct COW{    int t, d;} cow[maxn];bool cmp(COW a, COW b){    return a.t * b.d < a.d * b.t;}int main(){#ifdef LOCAL    freopen("in.txt", "r", stdin);#endif // LOCAL    int n;    while (~scanf("%d", &n))    {        LL sumD = 0;        for (int i = 0; i < n; i++)        {            scanf("%d%d", &cow[i].t, &cow[i].d);            sumD = sumD + (LL)cow[i].d;        }        sort(cow, cow + n, cmp);        LL ans = 0;        for (int i = 0; i < n; i++)        {            sumD -= cow[i].d;            ans = ans + 2 * sumD * (LL)cow[i].t;        }        printf("%lld\n", ans);    }    return 0;}

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