POJ 1016

//简单模拟，重点掌握string cin cout#include <iostream>#include <string>using namespace std;string calc(string str){int i, j = 0;int num[10] = {0};char inv[81];for(i = 0; i < str.length(); i++) //c++ !{num[str[i]-'0']++;}for(i = 0; i < 10; i++){if (num[i] > 0 && num[i] < 10) { inv[j++] = num[i] + '0'; inv[j++] = i + '0'; // i + 48 } else if (num[i] >= 10) { inv[j++] = num[i] / 10 + '0'; inv[j++] = num[i] % 10 + '0'; inv[j++] = i + '0'; }}inv[j] = '/0';return inv;}void funSolve(string str){int i, j;bool ok = false; //c++!string inv[16]; //???string temp = str; // c++! 相当于c中的strcpy(temp, str),方便不少。for(i = 0; i < 15; i++){temp = calc(temp);for(j = 0; j < i; j ++){if(temp == inv[j]) {ok = true;break;}}if(ok){if(i == 1 && j == 0){cout << str << " is self-inventorying" << endl;return; //用的很好！从当前函数跳转到调用该函数的任何地方.此时跳出函数。}else if(j == i - 1){cout << str << " is self-inventorying after " << i << " steps/n";return;}else{cout << str << " enters an inventory loop of length " << i - j << endl;return;}}inv[i] = temp;}cout << str << " can not be classified after 15 iterations/n";}int main(){char str[100];while (1 == scanf("%s", str)){//cin >> str;if(str[0] == '-')break;funSolve(str);}return 0;}

 

c++入门经典 第六章。