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POJ 3544 Journey with Pigs 贪心

热度:18   发布时间:2024-01-13 18:20:51.0

首先根据村庄离A的距离和单位路程的花费,以及当地猪肉的价格,我们可以把到达每一个村庄卖猪单位重量赚的钱算出来。然后,按收益降序排列,再把猪的重量降序排序,这时,根据排序不等式,就可以达到最大盈利了。

所谓排序不等式:

排序不等式(sequence inequality,又称排序原理

设有两组数 a1 , a2 ,…… an; b1 , b2 ,…… bn 满足 a1 ≤ a2 ≤……≤ an, b1 ≤ b2 ≤……≤ bn ,其中c1,c2,……,cn是b1,b2,……,bn的任一排列,则有

a1* bn + a2 *b{n-1}+ ... + an *b1

≤ a1 *c1 + a2* c2 +……+ an *cn

≤ a1 *b1 + a2 *b2 + ……+an* bn.

当且仅当 a1 = a2 = ... = an 或 b1 = b2 = ... = bn 时等号成立,即反序和等于顺序和。

以上排序不等式也可简记为: 反序和≤乱序和≤同序和.


/*
ID: sdj22251
PROG: calfflac
LANG: C++
*/
#include <iostream>
#include <vector>
#include <list>
#include <map>
#include <set>
#include <deque>
#include <queue>
#include <stack>
#include <bitset>
#include <algorithm>
#include <functional>
#include <numeric>
#include <utility>
#include <sstream>
#include <iomanip>
#include <cstdio>
#include <cmath>
#include <cstdlib>
#include <cctype>
#include <string>
#include <cstring>
#include <cmath>
#include <ctime>
#define LOCA
#define PI acos(-1.0)
using namespace std;
struct village
{__int64 price, dis, profit;int id;
}p[1001];
struct zhu
{__int64 weight;int id;
}pig[1001];
bool cmp1(village a, village b)
{return a.profit > b.profit;
}
bool cmp2(zhu a, zhu b)
{return a.weight > b.weight;
}
int main()
{
#ifdef LOCALfreopen("calfflac.in","r",stdin);freopen("calfflac.out","w",stdout);
#endifint n, i;__int64 t;scanf("%d%I64d", &n, &t);for(i = 0; i < n; i++){scanf("%I64d", &pig[i].weight);pig[i].id = i + 1;}sort(pig, pig + n, cmp2);for(i = 0; i < n; i++){scanf("%I64d", &p[i].dis);}for(i = 0; i < n; i++){scanf("%I64d", &p[i].price);p[i].id = i + 1;p[i].profit = p[i].price - p[i].dis * t;}sort(p, p + n, cmp1);int ans[1001];for(i = 0; i < n; i++){ans[p[i].id] = pig[i].id;}for(i = 1; i < n; i++)printf("%d ", ans[i]);printf("%d\n", ans[n]);return 0;
}