编辑代码

#include<stdio.h>
int main(){
int bs(int a[],int size,int p);
 int i,n,result;
int p=11;
int size=20;
int a[19];
for(i=1;i<=20;i++)
a[i]=i;
result=bs
(a,size,p);    
printf("%d",result);    
return 0;        
}
int bs(int a[],int size,int p)
{int l=0;int r=size-1;
while(l<=r){
int mid=l+(r-l)/2;
if(p==a[mid])
return mid;
else if(p>a[mid])
l=mid+1;
else r=mid-1;    
printf("mid = %d,l= %d,r = %d\n",mid,l,r);
}

return -1;        
}