Add solutions for problems 1920, 2769, 2894, and 3110

Author: DarkSnakeX

src/main/java/me/darksnakex/problems/p1920.java

@@ -0,0 +1,17 @@
+package me.darksnakex.problems;
+
+public class p1920 {
+
+
+    public int[] buildArray(int[] nums) {
+        int[] res = new int[nums.length];
+
+        for(int i = 0; i < nums.length; i++){
+            res[i]=nums[nums[i]];
+        }
+
+        return res;
+    }
+
+
+}

src/main/java/me/darksnakex/problems/p2769.java

@@ -0,0 +1,8 @@
+package me.darksnakex.problems;
+
+public class p2769 {
+
+    public int theMaximumAchievableX(int num, int t) {
+        return num+t+t;
+    }
+}

src/main/java/me/darksnakex/problems/p2894.java

@@ -0,0 +1,22 @@
+package me.darksnakex.problems;
+
+public class p2894 {
+
+    public int differenceOfSums(int n, int m) {
+        int res1 = 0;
+        int res2 = 0;
+
+        for(int i = 1; i <= n; i++){
+            if(i % m == 0){
+                res1+=i;
+            }else{
+                res2+=i;
+            }
+
+        }
+
+        return res2-res1;
+
+    }
+
+}

src/main/java/me/darksnakex/problems/p3110.java

@@ -0,0 +1,20 @@
+package me.darksnakex.problems;
+
+public class p3110 {
+
+    public int scoreOfString(String s) {
+        int res = 0;
+        int anterior = 0;
+
+        char[] charArray = s.toCharArray();
+
+        for(char car: charArray){
+            if(anterior != 0) {
+                res += Math.abs(car - anterior);
+            }
+            anterior = car;
+        }
+
+        return res;
+    }
+}