二分搜索(折半查找)
伪代码
function BinarySearch(List,key) {
left = 0,right = Lis.length - 1
while left <= right
mid = (left + right) / 2
if List[mid] is key
return mid
if List[mid] < key
left = mid + 1;
else
right = mid -1;
}
代码
#include <stdio.h>
int BinarySearch(int numbers[],int len,int key)
{
int left=1,right=len;
int mid;
while(left <= right){
mid=(left+right)/2;
if(numbers[mid]==key)
return mid;
else if(numbers[mid]<key)
left = mid+1;
else
right = mid-1;
}
return 0;
}
int main() {
int N;
int K;
int m;
int numbers[1000001];
// 反复读入数字和查找数字的数量
while (scanf("%d%d", &N, &K) != EOF) {
for (int i = 1; i <= N; i++)
scanf("%d", &numbers[i]);
for (int j = 0; j < K; j++) {
scanf("%d", &m);
printf("%d",BinarySearch(numbers,N,m));
if(j!=K-1)
printf(" ");
}
}
return 0;
}