Add solutions for problems 9, 171, 326, 338, 357, 1323, 2264, 2574, and 2798

Author: DarkSnakeX

src/main/java/me/darksnakex/problems/java/p1323.java

@@ -0,0 +1,27 @@
+package me.darksnakex.problems.java;
+
+
+public class p1323 {
+
+    public int maximum69Number (int num) {
+
+        char[] arr = Integer.toString(num).toCharArray();
+
+        for(int i = 0; i < arr.length; i++){
+            if(arr[i] == '6'){
+                arr[i] = '9';
+                break;
+            }
+        }
+
+        int res = 0;
+        int pow = 0;
+        for(int i = arr.length-1; i>= 0; i--){
+            res+= (int)(Math.pow(10,pow))*(arr[i]-48);
+            pow++;
+        }
+
+        return res;
+    }
+
+}

src/main/java/me/darksnakex/problems/java/p171.java

@@ -0,0 +1,19 @@
+package me.darksnakex.problems.java;
+
+public class p171 {
+
+    public int titleToNumber(String columnTitle) {
+
+        int res = 0;
+        int temp = 0;
+        for(int i = columnTitle.length()-1; i>=0; i--){
+            int numac = columnTitle.charAt(temp)-64;
+            res+= (int) (numac*Math.pow(26,i));
+            temp++;
+
+        }
+
+        return res;
+    }
+
+}

src/main/java/me/darksnakex/problems/java/p2264.java

@@ -0,0 +1,26 @@
+package me.darksnakex.problems.java;
+
+public class p2264 {
+
+    public String largestGoodInteger(String num) {
+
+        String res = "";
+        char anterior = 0;
+        char anterior2 = 0;
+        for(int i = 0; i < num.length(); i++){
+            if(anterior ==  anterior2 && anterior2 == num.charAt(i)) {
+                if(res.isEmpty() || num.charAt(i) > res.charAt(0)) {
+                    res = anterior2 + String.valueOf(anterior) + num.charAt(i);
+                    anterior = 0;
+                }
+            }
+            anterior2 = anterior;
+            anterior = num.charAt(i);
+        }
+
+
+        return res;
+
+    }
+
+}

src/main/java/me/darksnakex/problems/java/p2574.java

@@ -0,0 +1,49 @@
+package me.darksnakex.problems.java;
+
+import java.util.Arrays;
+
+public class p2574 {
+
+    public int[] leftRightDifference(int[] nums) {
+
+        int[] leftsum = new int[nums.length];
+        int[] rightsum = new int[nums.length];
+        int[] res = new int[nums.length];
+
+
+        int acumulado = 0;
+        int j = 1;
+        for(int i = 0; i < nums.length; i++){
+
+            if(i != 0) {
+                leftsum[j] = acumulado;
+                j++;
+            }
+            acumulado+= nums[i];
+        }
+
+        System.out.println(Arrays.toString(leftsum));
+
+        acumulado = 0;
+        j = nums.length-2;
+        for(int i = nums.length-1; i >= 0; i--){
+            if(i != nums.length-1) {
+                rightsum[j] = acumulado;
+                j--;
+            }
+            acumulado+= nums[i];
+        }
+
+        System.out.println(Arrays.toString(rightsum));
+
+        for (int i = 0; i < nums.length; i++){
+            res[i] = Math.abs(leftsum[i]-rightsum[i]);
+        }
+
+
+
+        return res;
+
+    }
+
+}

src/main/java/me/darksnakex/problems/java/p2798.java

@@ -0,0 +1,21 @@
+package me.darksnakex.problems.java;
+
+
+
+public class p2798 {
+
+
+    public int numberOfEmployeesWhoMetTarget(int[] hours, int target) {
+
+        int res = 0;
+        for (int hour : hours) {
+            if (hour >= target) {
+                res++;
+            }
+        }
+        return res;
+
+    }
+
+
+}

src/main/java/me/darksnakex/problems/java/p326.java

@@ -0,0 +1,21 @@
+package me.darksnakex.problems.java;
+
+public class p326 {
+
+    public boolean isPowerOfThree(int n) {
+
+        if(n == 0){
+            return false;
+        }
+
+        double res;
+        int res2;
+
+        res = (double) n /3;
+        res2 = n/3;
+
+        return res == res2;
+
+    }
+
+}

src/main/java/me/darksnakex/problems/java/p338.java

@@ -0,0 +1,17 @@
+package me.darksnakex.problems.java;
+
+public class p338 {
+
+    public int[] countBits(int n) {
+        int[] res = new int[n+1];
+
+        for(int i = n; i>0; i--){
+            res[i]=Integer.bitCount(n);
+            n--;
+        }
+
+
+        return res;
+    }
+
+}

src/main/java/me/darksnakex/problems/java/p357.java

@@ -0,0 +1,38 @@
+package me.darksnakex.problems.java;
+
+import java.util.HashSet;
+import java.util.Set;
+
+public class p357 {
+
+    public int countNumbersWithUniqueDigits(int n) {
+
+        int res = 0;
+        int max = (int) Math.pow(10,n);
+
+        for(int i = 0; i < max; i++){
+            if(!estaRepetido(Integer.toString(i))){
+                res++;
+            }
+        }
+
+        return res;
+
+    }
+
+    private boolean estaRepetido(String string) {
+        if (string.length() <= 1) {
+            return false;
+        }
+        Set<Character> set = new HashSet<>();
+        for (char car : string.toCharArray()) {
+
+            if (!set.add(car)) {
+                return true;
+            }
+        }
+
+        return false;
+    }
+
+}

src/main/java/me/darksnakex/problems/java/p9.java

@@ -0,0 +1,18 @@
+package me.darksnakex.problems.java;
+
+
+public class p9 {
+
+    public boolean isPalindrome(int x) {
+        String res = Integer.toString(x);
+        int j = res.length()-1;
+        for(int i = 0; i < res.length()/2; i++){
+            if(res.charAt(j) != res.charAt(i)){
+                return false;
+            }
+            j--;
+        }
+        return true;
+    }
+
+}