（挑战编程_5_7）The Stern-Brocot Number System

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#include <iostream>#include <cstdlib>#include <vector>#include <set>#include <string>#include <fstream>#include <cassert>using namespace std;//#define _MY_DEBUG_/*MainStructure: 主结构*/void MainStructure();/*Process：处理每一组数据*/void Process();/*计算*/string Calculate(unsigned num1, unsigned num2);int main(){MainStructure();return 0;}void MainStructure(){#ifdef _MY_DEBUG_string inputStr = "C:/Users/cao/Desktop/算法/要看的书/算法/2挑战编程/input/1.inp";//string inputStr = "D:/2挑战编程/input/110205.inp";string outputStr = "C:/Users/cao/Desktop/算法/要看的书/算法/2挑战编程/input/1.outp";ifstream fin;fin.open(inputStr);cin.rdbuf(fin.rdbuf());ofstream fout;fout.open(outputStr.c_str());cout.rdbuf(fout.rdbuf());#endifProcess();}void Process(){unsigned int num1, num2;while (cin >> num1 >> num2){if (num1 == 1 && num2 == 1){break;}cout << Calculate(num1, num2) << endl;}}string Calculate(unsigned m, unsigned n){string str;if (m == 1 && n == 1){return "I";}int leftUp = 0;int leftDown = 1;int rightUp = 1;int rightDown = 0;int middleUp = leftUp + rightUp;int middleDown = leftDown + rightDown;double fnum = (double)m / n;while (!(middleUp == m && middleDown == n)){double fmiddle = (double)middleUp / middleDown;if (fnum < fmiddle){str.append(1, 'L');rightUp = middleUp;rightDown = middleDown;}else if (fnum > fmiddle){str.append(1, 'R');leftUp = middleUp;leftDown = middleDown;}middleUp = leftUp + rightUp;middleDown = leftDown + rightDown;}return str;}