二叉查找（最简单的递归）

#include<iostream> #include<string> #include <set> using namespace std; #define N 5 int binal(int a[], int start, int end, int val) { if (start <= end) { int index = (start + end) / 2; if (a[index] == val) return val; if (a[index] > val) return binal(a, start, index - 1, val); if (a[index] < val) return binal(a, index + 1, end, val); } return -1; } int main() { int A[N] = { 1,3,5,7,9 }; cout << binal(A, 0, 4, 5) << endl; system("pause"); return 0; }