#include<stdio.h>
main()
{
    int c, n1, n2, n3;
    n1 = 0;
    n2 = 0;
    n3 = 0;
    while ((c = getchar())!= EOF)
    {
        if (c == ' ')
            ++n1;
        if (c == '\t')
            ++n2;
        if (c == '\n')
            ++n3;
    }
    printf("the blank space is %d;the tab is %d;the line break is %d" n1, n2, n3);
}

有啥疑问逆

printf("the blank space is %d;the tab is %d;the line break is %d"n1, n2, n3);  n1 前面少逗号

main前是不是需要加定义标识符呢