HDU 5281 BestCoder Round #47 1002-优快云博客

本文链接：https://blog.youkuaiyun.com/NMfloat/article/details/46845881

本文介绍如何运用贪心算法解决HDU在线编程平台上的问题，并提供了具体的实例代码，包括头文件引用、变量定义、算法实现以及输入输出处理。详细解释了排序数组的两种方式以及算法的核心逻辑，旨在帮助读者理解和掌握贪心算法的应用。

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Use greedy algorithm can solve this problem;

The portal:http://acm.hdu.edu.cn/showproblem.php?pid=5281

#include <cstdio>
#include <cstdlib>
#include <cstring>
#include <cmath>
#include <iostream>

using namespace std;

long long a[100005];
long long b[100005];

int cmp1(const void * a1,const void * a2){
	long long p1 = *(long long *)a1;
	long long p2 = *(long long *)a2;
	return p2 - p1;
}

int cmp2(const void * a1,const void * a2){
	long long p1 = *(long long *)a1;
	long long p2 = *(long long *)a2;
	return p1 - p2;
}


void Deal_with(){
	int T,n,m;
	scanf("%d",&T);
	while(T--){
		scanf("%d %d",&n,&m);
		for(int i=0;i<n;i++){
			scanf("%lld",a+i);
		}
		for(int i=0;i<m;i++){
			scanf("%lld",b+i);
		}
		qsort(a,n,sizeof(long long),cmp1);
		//Sort a array from higher to lower;
		qsort(b,m,sizeof(long long),cmp2);
		//Sort b array form lower to higher;
		int k = 0;
		long long ans = 0;
		for(int i=0;i<n;i++){
			if(k > m - 1)break;
			//I don't add this line that I can't pass the final test in BestCoder;
			if(a[i] < b[k])break;
			else {
				ans += a[i] - b[k++];
			}
		}
		printf("%I64d\n",ans);
	}
}

int main(void) {
	//freopen("a.in","r",stdin);
	Deal_with();
	return 0;
}