C语言中判断两数组中是否有相同的元素

#include <stdio.h>
#include <stdlib.h>
int main()
{
	int a[5] = {5,3,2,65,8};
	int b[8] = {78,8,9,56,3,6,0,7};
	int i = 0;
	int j = 0;
	int flag = 0;  //flag用于标记
	for (i = 0; i < 5; i++)
	{
		for (j = 0; j < 8; j++)
		{
			if (a[i] == b[j])
			  flag++;	
		}
	}
	if (flag == 0)
	    printf("两数组无相同元素\n");
	else
		printf("两数组有相同元素\n");
	system("pause");
	return 0;
}

#include <stdio.h>
#include <stdlib.h>
 
int main()
{
	int a[] = {34,24,78,5,3};
	int b[] = {23,7,98,5,23,3};
	int i = 0;
	int j = 0;
	for (i = 0; i < sizeof(a) / sizeof(a[0]); i++)//此时sizeof(a) / sizeof(a[0])=5
	{
		for (j = 0; j < sizeof(b) / sizeof(b[0]); j++)//此时sizeof(b) / sizeof(b[0])=6
		{
			if (a[i] == b[j])
			{
				printf("两数组有相同元素\n");
				system("pause");
				return 0;//存在相同元素就返回，减少循环结构的运行次数
			}
		}
	}
	if (i == sizeof(a) / sizeof(a[0]))
	printf("两数组无相同元素\n");
 
	system("pause");
	return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1 
#include<stdio.h>
#include<stdlib.h>
int main()
{
	int arr1[4] = {0};
	int arr2[5] = {0};
	int i = 0,j=0,k=0;
	printf("请输入数组1(4个元素)：\n");
	for(i = 0;i<sizeof(arr1)/sizeof(arr1[0]);i++)
	{
		scanf("%d",&arr1[i]);
	}
	printf("请输入数组2(5个元素)：\n");
	for(i=0;i<sizeof(arr2)/sizeof(arr2[0]);i++)
	{
		scanf("%d",&arr2[i]);
	}
 
	for(j = 0; j<sizeof(arr1)/sizeof(arr1[0]); j++)
	{
		for(k = 0;k<sizeof(arr2)/sizeof(arr2[0]);k++)
		{
			if(arr1[j] == arr2[k])
			{
				printf("有相同元素！\n");
			}
			if(k<sizeof(arr2)/sizeof(arr2[0]))	
			{
				break;
			}
		}
		if(j>=sizeof(arr1)/sizeof(arr1[0]))	
		printf("没有相同元素！\n");
	}
	return 0;
}

#define _CRT_SECURE_NO_WARNINGS 1 
#include<stdio.h>
#include<stdlib.h>
int main()
{
	int arr1[4] = {0};
	int arr2[5] = {0};
	int i = 0,j=0,k=0;
	printf("请输入数组1(4个元素)：\n");
	for(i = 0;i<sizeof(arr1)/sizeof(arr1[0]);i++)
	{
		scanf("%d",&arr1[i]);
	}
	printf("请输入数组2(5个元素)：\n");
	for(i=0;i<sizeof(arr2)/sizeof(arr2[0]);i++)
	{
		scanf("%d",&arr2[i]);
	}
 
	for(j = 0; j<sizeof(arr1)/sizeof(arr1[0]); j++)
	{
		for(k = 0;k<sizeof(arr2)/sizeof(arr2[0]);k++)
		{
			if(arr1[j] == arr2[k])
			{
				printf("有相同元素！\n");
				return 0;
			}
		}
	}
	printf("没有相同元素！\n");
	return 0;
}