Added TwoSum.java

Programming/C++/LetterCombinationofaPhoneNumber/letterCombination.cpp

@@ -0,0 +1,48 @@
+#include <iostream>
+#include <cstring>
+#include <vector>
+#include <unordered_map>
+using namespace std;
+
+vector <string> res;
+void possibleCombinations(string &digit,int index,unordered_map <int,string> &map,string &ans){
+    if(index == digit.length()){
+        res.push_back(ans);
+        return;
+    }
+    int current = digit[index] - '0';
+    string output = map[current];
+    for(int j=0; j<output.length(); j++){
+        ans.push_back(output[j]);
+        possibleCombinations(digit,index+1,map,ans);
+        ans.pop_back();
+    }
+}
+vector<string> letterCombinations(string digits) {
+        if(digits == "")
+            return {};
+        unordered_map <int,string> map;
+        map[2] = "abc";
+        map[3] = "def";
+        map[4] = "ghi";
+        map[5] = "jkl";
+        map[6] = "mno";
+        map[7] = "pqrs";
+        map[8] = "tuv";
+        map[9] = "wxyz";
+        string ans = "";
+        possibleCombinations(digits,0,map,ans);
+        return res;
+}
+int main()
+{
+    string digits;
+    cout << "Type digits in range of (2,9)";
+    cin >> digits; 
+    vector<string> fRes;
+    fRes = letterCombinations(digits);
+    for(auto i = fRes.begin(); i != fRes.end(); i++) {
+        cout<< *i << " "; 
+    }
+    return 0;
+}

Programming/Java/TwoSum/twoSum.java

@@ -0,0 +1,42 @@
+import java.util.ArrayList;
+import java.util.Scanner;
+
+public class Main {
+    public static void main(String[] args) {
+
+        Scanner sc = new Scanner(System.in);
+        System.out.println("Enter the array length: ");
+        int n = sc.nextInt();
+        int arr[] = new int[n];
+        System.out.println("Enter array elements (elements should be *Non-Decresing* order): ");
+        for (int i = 0; i < n; i++) {
+            arr[i] = sc.nextInt();
+        }
+        System.out.println("Enter a target sum: ");
+        int target = sc.nextInt();
+
+        twoSum(arr, n, target);
+
+    }
+
+    public static void twoSum(int[] arr, int n, int target) {
+        int left = 0, right = n - 1;
+        ArrayList<Integer> res = new ArrayList<Integer>(3);
+        while (left < right) {
+            int sum = arr[left] + arr[right];
+            if (sum == target) {
+                res.add(left);
+                res.add(right);
+                break;
+            } else if (sum > target) {
+                right--;
+            } else {
+                left++;
+            }
+        }
+        for (int i = 0; i < res.size(); i++) {
+            int ind = res.get(i);
+            System.out.print(ind + 1 + " ");
+        }
+    }
+}