二分查找

int BinarySearch(int fun[],int left,int right,int key){int middle;while(left<=right){middle=(left+right)/2;if(key==fun[middle])return 1;else if(key<fun[middle])right=middle-1;elseleft=middle+1;}return 0;}

简单二分查找，时间复杂度O(logN)。