二分查找和顺序查找

#include<bits/stdc++.h>
using namespace std;

int main() {
    int a[6];
    int key;
    for(int i=1;i<6;i++) cin >> a[i];
    cin >> key;
    int flag = 0;
    for(int i=1;i<5;i++) {
        if(a[i] == key) {
            cout << i << endl;
            flag = 1;
            break;
        }
    }
    if(flag == 0) cout << "0" << endl;
    return 0;
} 

#include<bits/stdc++.h>
using namespace std;

int main() {
    int a[6];
    int key;
    for(int i=1;i<6;i++) cin >> a[i];
    cin >> key;
    int flag = 0;
    int low=1,mid,high=6;
    while(low <= high) {
        mid=(low+high)/2;
        if(key == a[mid]) {
            flag = 1;
            cout << mid << endl;
            break;
        }
        if(key > a[mid]) {
            low = mid + 1;
        }
        if(key < a[mid]) {
            high = mid - 1;
        }
    } 
    if(flag == 0) cout << "0" << endl;
    return 0;
}