[算法练习]插入排序的C语言实现

#include <stdio.h>void insert_sort();int length;int n=0;int main(){int a[]={4,7,1,17,11,6,9,1,9,12};int i;length=sizeof(a)/sizeof(a[0]);printf("before:\t");for(i=0;i<length;i++)i!=length-1?printf("%d, ",a[i]):printf("%d",a[i]);printf("\n");insert_sort(a);printf("after:\t");for(i=0;i<length;i++)i!=length-1?printf("%d, ",a[i]):printf("%d",a[i]);getchar();}void insert_sort(int arr[]){int i,j,key,index;for (i=1;i<length;i++){//key <- arr[i]key = arr[i];//insert key into sorted arrfor(j=0;j<i;j++){n++;if(key<=arr[j]){//if key<a[j] then insert key to index jfor(index=i;index>j;index--){//arr[i]<-arr[i-1]arr[index]=arr[index-1];}arr[j]=key;break;//next key}}}}