交换两个数组的元素使之总和的差值最小

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题目描述：

有两个数组a,b，大小都为n,数组元素的值任意整型数，无序；
要求：通过交换a,b中的元素，使数组a元素的和与数组b元素的和之间的差最小。

#include "stdafx.h"#include <math.h>#include <time.h>#include <stdlib.h>void print_arr(int a[], int b[], int n){printf("a: ");for (int i=0;i<n;i++){printf("%d ", a[i]);}printf("\n");printf("b: ");for (int i=0;i<n;i++){printf("%d ", b[i]);}printf("\n");printf("\n");}bool swap_min(int a[], int b[], int n){printf("before swap:\n");print_arr(a, b, n);// 初始化差值int sum_a=0;int sum_b=0;for (int k=0;k<n;k++){sum_a += a[k];sum_b += b[k];}int delta_init = abs(sum_a - sum_b);for (int i=0;i<n;i++){/*if (delta_init == 0) // 优化处理{break;}*/int sum_a=0;int sum_b=0;for (int k=0;k<n;k++){sum_a += a[k];sum_b += b[k];}// 假设交换，差值是否更小bool bswp = false;int jpos = 0;for (int j=0;j<n;j++){int sum_atemp = sum_a-a[i]+b[j];int sum_btemp = sum_b-b[j]+a[i];int delta_temp = abs(sum_atemp-sum_btemp);if (delta_temp < delta_init){delta_init = delta_temp;jpos = j;bswp =true;}}// 假设成功，执行交换元素if (bswp){int tmp = a[i];a[i] = b[jpos];b[jpos] = tmp;}}printf("after swap:\n");print_arr(a,b,n);return true;}int _tmain(int argc, _TCHAR* argv[]){int a[5] = {0, 0, 0, 0, 9};//1,2,3,4,5int b[5] = {1, 2, 5, 4, 3};//6,7,8,9,100int c[] = {1,2,3,4,5};int d[] = {6,7,8,9,100};int e[]={1,2,3,4,5};int f[]={10,20,30,40,50};////////////////////////swap_min(a, b, 5);swap_min(c, d, 5);swap_min(e, f, 5);errno_t err;  unsigned int number;  err = rand_s(&number);  int m[100];int n[100];srand( (unsigned)time(NULL)); //生成种子for (int i=0;i<100;i++){m[i]=rand()%100;n[i]=abs(rand()%200-100);}swap_min(m, n, 10);////////////////////////getchar();return 0;}

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