[C How To Program] 习题6.35 二分查找

#include <stdio.h>#define N 10void swap(int *a, int *b){int tmp = *a;*a = *b;*b = tmp;}void asort(int *a ,int n){int i, j;for(i = 1; i < n;i++){for( j = 0; j <= n - i - 1; j++){if(a[j] > a[j + 1]){swap( &a[j], &a[j + 1]);}}}}void printA(int *a, int n){int i;for(i = 0; i < n; i++){printf("[%d]:%d ", i, a[i]);}printf("\n");}int bSearch(int *a , int n, int key){int start = 0 ,end = n, mid;while( start <= end){mid = (start + end) / 2;if( a[mid]  == key){return mid;}else if(a[mid] > key){end = mid - 1;}else{start = mid + 1;}}return -1;}int main(){int i, a[N] = {0};srand(time(NULL));for(i = 0; i < N; i++){a[i] = rand() % 100;}printA(a, N);asort(a, N);printA(a, N);for(i = 0; i < N; i++){printf("%d in a[%d]\n", a[i], bSearch(a, N, a[i]));}}