PTA统计素数并求和问题

Question

pta的作业，显示部分正确，自己盯着看不出来了。。可以帮忙指正一下吗？
谢谢谢谢！

#include
#include
int main (void)
{
int m, n, flag = 1, c = 0, s = 0;
scanf ("%d %d",&m,&n);
for (int i = m;i <= n;i++) {
for (int j = 2;j <= i / 2;j++){
if (i % j == 0){
flag = 0;
break;
}
}
if (flag == 1){
c++;
s += i;
}
}
printf ("%d %d",c,s);
return 0;
}

Answer 1

flag = 0;要放在循环for (int i = m;i <= n;i++)的里面

#include <stdio.h>
#include <math.h>
int main (void)
{
    int m, n, flag = 1, c = 0, s = 0;
    scanf ("%d %d",&m,&n);
    for (int i = m;i <= n;i++) {
        flag=1;
        for (int j = 2;j <= i / 2;j++){
            if (i % j == 0){
                flag = 0;
                break;
            }
        }
        if (flag == 1){
            c++;
            s += i;
        }
    }
    printf ("%d %d",c,s);
    return 0;
}