C语言实现常用查找算法——二分查找

#include<stdio.h>
void insert_sort(int a[],int n);
int binary_search(int a[],int x,int n);
void print_array(int a[],int n);

main() {
    int a[]= {4,-3,2,-5,7,-32,90,1,-8,43,-9,2};
    int n=sizeof(a)/sizeof(0);
    int x=43;
    print_array(a,n);
    insert_sort(a,n);
    print_array(a,n);
    int m=binary_search(a,x,n);
    printf("%d",m);
}
/*插入排序*/
void insert_sort(int a[],int n) {
    int i,j;
    for(i=1; i<n; i++) {
        int temp=a[i];
        for(j=i; j>0&&a[j-1]>temp; j--) {
            a[j]=a[j-1];
        }
        a[j]=temp;
    }
}
/*二分查找*/
int binary_search(int a[],int x,int n) {
    int low,center,high;
    low=0;
    high=n-1;
    while(low<high) {
        center=(low+high)/2;
        if(a[center]==x) {
            return center;
        } else if(a[center]>x) {
            high=center-1;
        } else {
            low=center+1;
        }
    }
    return -1;
}
/*打印数组*/
void print_array(int a[],int n) {
    int i;
    for(i=0; i<n; i++) {
        printf("%d ",a[i]);
    }
    printf("%c",'\n');
}

 

posted @ 2018-09-07 11:19  Mars.wang  阅读(5572)  评论(0编辑  收藏  举报