C :

#include<stdio.h>
int main()
{
    int n,a[10],i,b,low,high,mid;
    for(i=0;i<10;i++)
        scanf("%d",&a[i]);
    while(~scanf("%d",&n))
        {
            while(n--)
            {
                scanf("%d",&b);
                low=1;high=9;
                if(b==a[0])
                    printf("1\n");
                else
                {
                    while(low<=high)
                    {
                        mid=(low+high)/2;
                        if(a[mid]==b)
                        {printf("%d\n",mid+1);break;}
                        else if(a[mid]>b)
                            high=mid-1;
                        else low=mid+1;
                    }
                }
                if(low>high)
                    printf("error\n");
             }
        }
        return 0;
}

C++ :

#include<iostream>

using namespace std;

int a[15];
int flag;

int zb(int n){
    int left,right,mid;
    left = 1;
    right = 10;
    //mid = (left + right) / 2;
    while(left <= right){
        int mid = (left + right) / 2;
        if(a[mid]<n){
            left = mid + 1;
        }
        else if(a[mid]>n){
            right = mid - 1;
        }
        else
            return mid;
        //cout<<left<<' '<<right<<' '<<mid<<endl;
    }
    flag = 0;
    //cout<<flag<<endl;
    return -1;
}

int main(){
    for(int i=1;i<11;i++)
        cin>>a[i];
    int n;
    cin>>n;
    while(n--){
        flag = 1;
        int m;
        cin>>m;
        //cout<<flag<<endl;
        int x = zb(m);
        if(!flag)
            cout<<"error"<<endl;
        else
            cout<<x<<endl;
    }
    return 0;
}

Java :

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner sc = new Scanner(System.in);
		int[] a = new int[10];
		for(int i=0;i<10;i++) {
			a[i] = sc.nextInt();
		}
		
		int n = sc.nextInt();
		int b;
		for(int i=0;i<n;i++) {
			b = 0;
			int c=0;
			b = sc.nextInt();
			for(int j=0;j<10;j++) {
				if(b == a[j]) {
					c++;
					System.out.println(j+1);
					break;
				}
			}
			if(c==0) {
				System.out.println("error");
			}
		}
		
		
		
	}

}