int compare(const void *a,const void *b) { return *(int *)a-*(int *)b; } //二分查找离元素(可以等于) int bi_search(int num[10], int len, int target) { <span style="white-space:pre"> </span>int begin = 0; <span style="white-space:pre"> </span>int end = len-1;<span style="white-space:pre"> </span> <span style="white-space:pre"> </span>while(begin<end) <span style="white-space:pre"> </span>{ <span style="white-space:pre"> </span>int mid = (begin+end)/2; <span style="white-space:pre"> </span>cout<<mid<<" "<<target<<endl; <span style="white-space:pre"> </span>cout<<mid<<" "<<len-1<<endl; <span style="white-space:pre"> </span>//最近的一个 <span style="white-space:pre"> </span>if(num[mid]==target) <span style="white-space:pre"> </span>return mid; <span style="white-space:pre"> </span>else if(num[mid]>target) <span style="white-space:pre"> </span>end = mid-1; <span style="white-space:pre"> </span>else <span style="white-space:pre"> </span>begin = mid+1; <span style="white-space:pre"> </span>} <span style="white-space:pre"> </span>cout<<"begin:"<<begin<<"end:"<<end<<endl; <span style="white-space:pre"> </span>return end; } void main() { int num[10]={11,35,65,25,79,54,34,66,92,30}; qsort(num,10,sizeof(int),compare); for(int i=0;i<10;i++) cout<<num[i]<<" "; cout<<endl; int index = bi_search(num, 10, 36); cout<<index<<endl; }