100 - The 3n + 1 problem

#include <iostream>
using namespace std;
 
int calc_cycle_length(int n) {
    int cycle_length = 1;
    while (n != 1) {
        if (n == 1) {
            return false;
        } else if (n % 2 != 0) {
            n = 3 * n + 1;
        } else {
            n = n / 2;
        }
        cycle_length++;
    }
    return cycle_length;
}
 
int main() {
    int firstNum, endNum;
    int temp = 0;
    int cycleLength = 0;
    int maxLength ;
    while (cin >> firstNum >> endNum && (firstNum != 0 || endNum != 0)) {
        cout<<firstNum<<" "<<endNum<<" ";
        maxLength = 0;
        if (firstNum > endNum) {
            temp = endNum;
            endNum = firstNum;
            firstNum = temp;
        }
        for (int i = firstNum; i < endNum; i++) {
            cycleLength = calc_cycle_length(i);
            if (cycleLength > maxLength) {
                maxLength = cycleLength;
            }
        }
        cout<<maxLength<<"\n";
    }
 
    return 0;
 
}

拿到瘋狂程設run有一筆99999 99999這筆測資出不來，瘋狂程設這筆結果是要輸出227，但我只能輸出0..... 題目網址http://bit.ly/2eOC6q1