C :

#include<stdio.h>
#include<string.h>

int main()
{
	int t,i,n;
	char a[100];
	scanf("%d",&t);
	while(t--)
	{
		memset(a,'0',sizeof(a));
		scanf("%s%d",a,&n);
		for(i=0,a[strlen(a)]='0';;i++)
			if(a[i]=='.')
				break;
		printf("%c\n",a[i+n]);
	}
	return 0;
}

C++ :

#include<stdio.h>
#include<string.h>

int main()
{
	int t,i,n;
	char a[100];
	scanf("%d",&t);
	while(t--)
	{
		memset(a,'0',sizeof(a));
		scanf("%s%d",a,&n);
		for(i=0,a[strlen(a)]='0';;i++)
			if(a[i]=='.')
				break;
		printf("%c\n",a[i+n]);
	}
	return 0;
}

Java :

import java.util.Scanner;

public class Main {

	public static void main(String[] args) {
		Scanner in = new Scanner(System.in);
		int t = Integer.parseInt(in.nextLine());
		while(t-->0){
			String s = in.nextLine();
			String[] ss = s.split(" ");
			int cou = Integer.parseInt(ss[1]);
			String[] ss1 = ss[0].split("\\.");
			try{
				System.out.println(ss1[1].charAt(cou-1));
			}catch( java.lang.StringIndexOutOfBoundsException e){
				System.out.println(0);
			}
		}
	}

}