C语言的一个问题，求大家帮帮忙

Question

为什么这个变量范围在999及以内但输出结果有四位数？
输出结果是：153，370，371，407，1000，10001

```c
#include <stdio.h>
#include <stdlib.h>
#include <windows.h>

int main () {
    int one, two, three, four;
    
    for (four = 100; four = four + 1; four <= 999) {
        two = four / 100; //百位

        three = four / 10 % 10; //十位

        one = four % 10; //个位

        if (four == two * two * two + three * three * three + one * one * one) {
            printf("%d\n", four);
        }
    }

    system("pause");

    return 0;

}

Answer 1

第10行： for (four = 100; four = four + 1; four <= 999) 条件语句 和 自增语句 放错位置了，互换下：
for (four = 100; four <= 999;four = four + 1)