1、
#include <stdio.h>
int main(void)
{
int i, j, x, y, z;
do
{
puts("please input an integer.");
printf("x = "); scanf("%d", &x);
}
while (x < 0 || x > 100);
putchar('\n');
y = x; z = x;
while ( y >= 0)
{
printf("y:%d z:%d\n", y--, z++);
}
printf("\nsquare is %d.\n", x);
printf("the propable sides i are :\n");
for (i = 1; i <= x; i ++)
{
if (i * i > x)
break;
if (x % i != 0)
continue;
printf("side1:%d side2:%d\n", i, x / i);
}
printf("\ndraw a star tangle!\n");
for (i = 1; i <= 3; i ++)
{
for (j = 1; j <= 5; j++)
{
putchar('*');
}
putchar('\n');
}
return 0;
}