InfyTQ - Java Coding Questions

import java.io.BufferedReader;
import java.io.InputStreamReader;
public class Question1 {
    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String str[] = br.readLine().split(“, ”);
        int num1 = 0;
        String num2 = ””;
        int n = str.length;
        int arr[] = new int[n];
        int fiveIndex = -1;
        int eightIndex = -1;
        for (int i = 0; i < n; i++) //converting string array into Integer array.
        {
            arr[i] = Integer.parseInt(str[i]);
            if (arr[i] == 5) // finding index of 5 in array
                fiveIndex = i;
            else if (arr[i] == 8)
                eightIndex = i; // finding index of 8 in array
        }
        for (int i = fiveIndex; i <= eightIndex; i++) {
            num2 += str[i]; //concatenating all values between 5 and 8 in the array.
            arr[i] = 0; //after concatenation we are assigning zero at that index because
            //we don’t need that value any more.
        }
        for (int num: arr) {
            num1 += num; //here we are adding all values. we have assigned zero in above loop
            //between fiveIndex and eightIndex in the arr.so it will add remaining outer values.
        }
        System.out.println(num1 + (Integer.parseInt(num2))); //print the sum!
    }
}

	
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.Collections;
import java.util.HashSet;
public class Question2 {
    static boolean isDigit(char digit) {
        if (digit >= ‘0’ && digit <= ‘9’) return true;
        return false;
    }
    public static void main(String[] args) throws Exception {
            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            String input = br.readLine();
            StringBuilder sb = new StringBuilder();
            HashSet < Integer > hs = new HashSet < > ();
            for (int i = 0; i < input.length(); i++) {
                if (isDigit(input.charAt(i))) {
                    String dig = String.valueOf(input.charAt(i));
                    hs.add(Integer.parseInt(dig));
                }
            }
            ArrayList < Integer > digitList = new ArrayList < > (hs);
            Collections.sort(digitList, Collections.reverseOrder());
            int len = digitList.size();
            boolean evenDigitFound = false;
            for (int i = len - 1; i >= 0; i—) {
                int digit = digitList.get(i);
                if (digit % 2 == 0) {
                    digitList.remove(i);
                    digitList.add(digit); //adding even digit at end
                    evenDigitFound = true;
                    break;
                }
            }
            if (evenDigitFound == false) {
                System.out.print(-1);
            } else {
                for (int dig: digitList) System.out.print(dig); // printing largest even digits}}}
  

	
import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.HashSet;
public class Question4 {
    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        int n = Integer.parseInt(br.readLine());
        String strArr[] = br.readLine().split(“, ”);
        int len = strArr.length;
        HashSet < Integer > hs = new HashSet < > ();
        for (int i = 0; i < len; i++) {
            hs.add(Integer.parseInt(strArr[i]));
        }
        System.out.println(hs.size() - n);
    }
}
	

	
import java.io.BufferedReader;
import java.io.InputStreamReader;
public class Question9 {
    public static void main(String[] args) throws Exception {
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        String str = br.readLine();
        int length = str.length();
        int half = length / 2;
        for (int i = half; i >= 0; i—) {
            String prefix = str.substring(0, i);
            String suffix = str.substring(length - i, length);
            if (prefix.equals(“”) || suffix.equals(“”)) {
                System.out.println(“-1”);
                break;
            }
            if (prefix.equals(suffix)) {
                System.out.println(prefix);
                break;
            }
        }
    }
}

	
  import java.io.BufferedReader;
import java.io.InputStreamReader;
import java.util.HashSet;
public class Question10 {
    public static void main(String[] args) throws Exception {
            BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
            int testcase = Integer.parseInt(br.readLine());
            while (testcase— != 0) {
                int n = Integer.parseInt(br.readLine());
                String str[] = br.readLine().split(““);
                HashSet < String > hs = new HashSet < > ();
                int arr[] = new int[n];
                for (int i = 0; i < n; i++) arr[i] = Integer.parseInt(str[i]);
                for (int i = 0; i < n; i++) {
                    int sum = arr[i];
                    if (sum % 2 != 0) hs.add(arr[i] + ”“);
                    StringBuilder sb = new StringBuilder();
                    sb.append(arr[i]);
                    for (int j = i + 1; j < n; j++) {
                        sum += arr[j];
                        sb.append(arr[j]);
                        if (sum % 2 != 0) hs.add(sb.toString());
                    }
                }
                System.out.println(hs.size()); //that will be the no of unique subarray}}}