c语言数链问题，求解惑

Question

Answer 1

代码如下，如有帮助，请帮忙采纳一下，谢谢。

#include <stdio.h>

//计算链长
int getLength(int n)
{
    if(n==1)
        return 1;
    else
    {
        if(n%2==0)
            n = n/2;
        else
            n = 3*n+1;
        return 1+getLength(n);
    }
}

int main()
{
    int i,j,t,len,maxlen = 0;
    FILE* fp = fopen("link.in","r"); 
    if(fp == 0) {printf("file open error\n");return 0;}
    fscanf(fp,"%d %d",&i,&j);//从文件读取i和j的值
    fclose(fp);
    for(t = i;t<=j;t++)
    {
        len = getLength(t);
        if(len > maxlen) maxlen = t;
    }
    printf("%d",maxlen);
    return 0;
}