四则运算

include <stdio.h>

include <stdlib.h>

include <time.h>

include <math.h>

int main()
{
int i=0;
int n=0;
int x=0;
int type;
char flag;
int left, right;
float result;

printf("请输入要出的题目数量\n");
scanf("%d",&n);

srand(unsigned(time(NULL)));

while(x<n)
{
type = rand() % 4;
left = rand() % 100;
right = rand() % 100;
switch(type)
{
case 0:
printf("%d + %d = ?\n", left, right);
break;
case 1:
printf("%d - %d = ?\n", left, right);
break;
case 2:
printf("%d * %d = ?\n", left, right);
break;
case 3:
printf("%d / %d = ?\n", left, right);
break;
}

i++;
while(i>=n)
{
printf("一共 %d 题\n",i);
printf("继续?[Y/N]\n");
fflush(stdin);
scanf("%c",&flag);
if(flag'Y'||flag'y')
{
printf("请输入要出的题目数量\n");
scanf("%d",&n);
i=0;
break;
}
printf("谢谢使用！\n");
fflush(stdin);
getchar();
return 0;
}
}
}