分解质因数

#include <stdio.h>
#include <windows.h>

int fun22(int * a)
{
	int i, j, m = 0, true_ = 0;
	
	for(i = 2; i < 10000; i++)
	{
		true_ = 0;
		for(j = 2; j < i / 2 + 1; j++)
		{
			if(i % j == 0)
				true_ = 1;	
		}
		if(!true_)
			a[m++] = i;	
	}
	return m;
}

void fun21(void)
{
	int n, m, x, y;
	int i, j, true_;
	int a[5000], k, b[10000], kk = 0;
	
	scanf("%d%d", &n, &m);
	k = fun22(a);
	for(n ; n <= m; n++)
	{
		j = n;	true_ = 0;
		for(i = 0; i < k; i++)
		{
			if(n == a[i])
			{
				printf("%d=%d\n", n, n);
				true_ = 1;
				break;
			}		
		}
		if(true_)
			continue;
		memset(b, 0, sizeof(b));
		kk = 0; i = 0;
		while (i < k)
		{
			x = j / a[i];
			true_ = 0;
			if(j == a[i] * x)
			{
				j = x;
				
				b[kk++] = a[i];
				y = j / a[i]; 	
				if(j != 0 && j == y * a[i])
					true_ = 1;			
			}
			if(j == 0 || a[i] > n)
				break; 
			if(true_)
				i = 0;
			else
				i++; 
		}
		printf("%d=", n);
		for(i = 0; i < kk; i++)
		{
			if(i == kk - 1)
				printf("%d", b[i]);
			else 
				printf("%d*", b[i]);

                        //printf("%d%c", b[i], n == kk - 1 ? '*': '');
		}
		if(n < m)
			printf("\n");
	}
}

int main()
{	
	system("color 0a");	
	fun21();
	return 0;
}