为啥我输入完数据之后按回车不运行

# include<stdio.h>
int main()
{
    int i,a[500],x,flag,c,n,m;
    c = 0;
    scanf("%d,%d",&n,&m);
    for(x = 2;x<=1000;x++)
    {
    flag = 0;
        if(x%3==0)
        flag = 1;
    if(flag==1)
    {
        a[c] = x;
      c++;
    }
    }
    for(i = 0;i>=n&&i<=m;i++)
    printf("%d",a[i]);
    return 0;
}

结果如下：

for (i = 0; i >= n && i <= m; i++)这个循环进不去啊
i不满足 i >= n && i <= m这个条件直接退出循环了

# include<stdio.h>
int main()
{
    int i, a[500], x, flag, c, n, m;
    c = 0;
    scanf("%d,%d", &n, &m);
    for (x = 2; x <= 1000; x++)
    {
        flag = 0;
        if (x % 3 == 0)
            flag = 1;
        if (flag == 1)
        {
            a[c] = x;
            c++;
        }
    }
    for (i = n; i <= m; i++)  //从n开始，循环到m结束
        printf("%d ", a[i]);
    return 0;
}