HDOJ 1032 The 3n + 1 problem（水）

【题意】：获得最大循环长度。

【注意】：题目并不是一定按照第一二个数小于等于第二个数输入。如果不是，需要交换。。虽然这种数据感觉很无聊不过在题目中有提示的，The integers i and j must appear in the outputin the same order in which they appeared in the input and should be followed by the maximum cycle length (on the same line). 

【AC代码】：

#include <iostream>#include <cstdlib>#include <cstdio>#include <cstring>#include <cmath>#include <iomanip>using namespace std;/* run this program using the console pauser or add your own getch, system("pause") or input loop */int getLength(int a){int cnt = 1;while (a!=1){cnt++;//evenif (0==a%2)a = a/2;elsea = 3*a+1;}return cnt;}int main(int argc, char** argv) {//freopen("in.txt", "r", stdin);//freopen("out.txt", "w", stdout);int a = 0, b = 0;while (cin >> a >> b){int m = 0, n = 0;m = a < b?a:b;n = a < b?b:a;int i = 0, max = -1;for (i = m; i <=n; i++){if (max < getLength(i))max = getLength(i);}cout << a << " " << b << " " << max << endl;}return 0;}