基于C++的几个递归函数运用（.cpp）

#include <iostream> using namespace std; int sum = 0;//记录有多少种组合 void Swap(char str[], int a, int b) { char temp = str[a]; str[a] = str[b]; str[b] = temp; } bool IsSwap(char* pchar, int nBegin, int nEnd)//判断字符是否相同 { for (int i = nBegin; i < nEnd; i++) if (pchar[i] == pchar[nEnd]) return false; return true; } void Perm(char str[], int begin, int end) { if (begin == end) { for (int i = 0; i <= end; i++) { cout << str[i]; } cout << endl; sum++; return; } else { for (int j = begin; j <= end; j++) { if (IsSwap(str, begin, j))//如果不相同 进行交换 { Swap(str, begin, j); Perm(str, begin + 1, end); Swap(str, j, begin); } } } } int main() { int n; char c[16]; char tmp; cin >> n; tmp = getchar(); // 接受回车 if (1 <= n && n <= 15) { for (int i = 0; i < n; i++) { c[i] = getchar(); } Perm(c, 0, n - 1); } cout << sum; cout << endl; return 0; }