C language programming> twenty-fifth week ⑥ Please add the function fun. The function of this function is to count the number of prime numbers less than or equal to x (x>2), and the number of prime numbers is returned as the function value.

Example: Please add the function fun. The function of this function is to count the number of prime numbers less than or equal to x (x>2), and return the number of prime numbers as the function value.

例如，输入x=20,结果：2，3，5，7，11，13，17，19。
请勿改动主函数main与其他函数中的任何内容，仅在fun函数的横线上填写所需的若干表达式或语句。

代码如下：

#include<stdio.h>
int fun(int x)
{
    
    
	int i,j,count=0;
	printf("\nThe prime number between 2 to %d\n",x);
	for(i=2;i<=x;i++)
	{
    
    
		for(j=2;j<i;j++)
			if(i%j==0)
				break;
		if(j>=i)
		{
    
    
			count++;
			printf(count%15?"%5d":"\n%5d",i);
		}
	}
	return count;
}
main()
{
    
    
	int x=20,result;
	result=fun(x);
	printf("\nThe number of prime is:%d\n",result);
}

The output running window is as follows:

other exercises this week

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C language programming> twenty-fifth week ⑥ Please add the function fun. The function of this function is to count the number of prime numbers less than or equal to x (x>2), and the number of prime numbers is returned as the function value.

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越努力越幸运！
加油，奥力给！！！