>>11
#include <stdio.h>
int main()
{
int width, height, i, j;
printf("幅？:");
scanf("%d", &width);
printf("高さ？:");
scanf("%d", &height);
for(i = 0; i < height; i++){
for(j = 0; j < width; j++)
if(i == 0 || i == height - 1 || j == 0 || j == width - 1)
printf("*");
else
printf(" ");
printf("\n");
}
return 0;
}