The positive integer is decomposed into prime factors, such as 90 = 2 * 3 * 3 * 5 format output

#include <stdio.h>
#include <stdlib.h>


void main()
{
	int num;
	int fc[100];
	int i = 2,j,k=0,n;
	
	printf("输入一个正整数:");
	scanf("%d",&num);
	
	printf("%d=",num);
	
	while(num != 1)//判断循环结束的条件是正整数已经除完 
	{
		if(num % i==0)
		{
			for(j=2;j<=i/2;j++)
			{
				if(i%j==0)//因数不是质数则因数，跳出此层循环 
				break;
			}
			fc[k++] = i;
		    num = num/i;	
		}
		else
		    i++;//i不是因数，自增直到找到因数 
	
	}
	n = k;
	for(i=0;i<n-1;i++)
	{
	 printf("%d",fc[i]);
	 printf("*");
	}
	printf("%d",fc[n-1]);
}

operation result