KY199 查找C

C写个快排就行了。

#include<stdio.h>
#include<stdlib.h>
#include<stdbool.h>
int divide(int* A,int head, int tail){
    if(head==tail) return  head ;
    int x =A[head];
    while(head < tail){
        while(head < tail && A[tail] > x) tail--;
        if(head < tail) A[head++]=A[tail];
        while(head < tail && A[head] < x) head++;
        if(head < tail) A[tail--]=A[head];
    }
    A[head]=x;
    return head;
}

void quicksort(int* A, int head, int tail){
    if(head >= tail) return;
    int x= divide(A,head,tail);
    if(x>head) quicksort(A,head,x-1);
    if(x<tail) quicksort(A,x+1,tail);
}

bool judge(int* A , int n ,int x){
    int head =0;
    int tail=n-1;
    while(head<=tail){
        int mid = (head+tail)/2;
        if(A[mid]==x){
            return true;
        }else if(A[mid] < x){
            head=mid+1;
        }else{
            tail=mid-1;
        }
    }
    return false;
}

int main(){
    int n ;
    while(scanf("%d",&n) != EOF){
        int* A=(int*)malloc(sizeof(int )*n);
        for(int i = 0 ;i < n ;i++){
            scanf("%d",&A[i]);
        }
        quicksort(A,0,n-1);
        int m;
        scanf("%d",&m);
        for(int i =0;i<m;i++){
            int t;
            scanf("%d",&t);
            if(judge(A,n,t)){
                printf("YES\n");
            }else{
                printf("NO\n");
            }
        }
    }

    return 0;
}

结果如下：