add 1252

Author: fishercoder1534

README.md

@@ -27,6 +27,7 @@ Your ideas/fixes/algorithms are more than welcome!
 
 |  #  |      Title     |   Solutions   | Time          | Space         | Video  | Difficulty  | Tag                   
 |-----|----------------|---------------|---------------|---------------|--------|-------------|-------------
+|1252|[Cells with Odd Values in a Matrix](https://leetcode.com/problems/cells-with-odd-values-in-a-matrix/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1252.java) | O(m*n) | O(1) | |Easy||
 |1207|[Unique Number of Occurrences](https://leetcode.com/problems/unique-number-of-occurrences/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1207.java) | O(n) | O(1) | |Easy||
 |1160|[Find Words That Can Be Formed by Characters](https://leetcode.com/problems/find-words-that-can-be-formed-by-characters/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1160.java) | O(n) | O(m) | |Easy||
 |1154|[Day of the Year](https://leetcode.com/problems/day-of-the-year/)|[Solution](../master/src/main/java/com/fishercoder/solutions/_1154.java) | O(1) | O(1) | |Easy||

src/main/java/com/fishercoder/solutions/_1252.java

@@ -0,0 +1,66 @@
+package com.fishercoder.solutions;
+
+/**
+ * 1252. Cells with Odd Values in a Matrix
+ *
+ * Given n and m which are the dimensions of a matrix initialized by zeros and given an array indices where indices[i] = [ri, ci]. For each pair of [ri, ci] you have to increment all cells in row ri and column ci by 1.
+ * Return the number of cells with odd values in the matrix after applying the increment to all indices.
+ *
+ * Example 1:
+ * 0, 0, 0     1, 2, 1    1, 3, 1
+ * 0, 0, 0     0, 1, 0    1, 3 ,1
+ *
+ * Input: n = 2, m = 3, indices = [[0,1],[1,1]]
+ * Output: 6
+ * Explanation: Initial matrix = [[0,0,0],[0,0,0]].
+ * After applying first increment it becomes [[1,2,1],[0,1,0]].
+ * The final matrix will be [[1,3,1],[1,3,1]] which contains 6 odd numbers.
+ *
+ * Example 2:
+ * 0, 0    0, 1    2, 2
+ * 0, 0    1, 2    2, 2
+ *
+ * Input: n = 2, m = 2, indices = [[1,1],[0,0]]
+ * Output: 0
+ * Explanation: Final matrix = [[2,2],[2,2]]. There is no odd number in the final matrix.
+ *
+ *
+ * Constraints:
+ * 1 <= n <= 50
+ * 1 <= m <= 50
+ * 1 <= indices.length <= 100
+ * 0 <= indices[i][0] < n
+ * 0 <= indices[i][1] < m
+ * */
+public class _1252 {
+    public static class Solution1 {
+        public int oddCells(int n, int m, int[][] indices) {
+            int[][] matrix = new int[n][m];
+            for (int i = 0; i < indices.length; i++) {
+                addOneToRow(matrix, indices[i][0]);
+                addOneToColumn(matrix, indices[i][1]);
+            }
+            int oddNumberCount = 0;
+            for (int i = 0; i < matrix.length; i++) {
+                for (int j = 0; j < matrix[0].length; j++) {
+                    if (matrix[i][j] % 2 != 0) {
+                        oddNumberCount++;
+                    }
+                }
+            }
+            return oddNumberCount;
+        }
+
+        private void addOneToColumn(int[][] matrix, int columnIndex) {
+            for (int i = 0; i < matrix.length; i++) {
+                matrix[i][columnIndex] += 1;
+            }
+        }
+
+        private void addOneToRow(int[][] matrix, int rowIndex) {
+            for (int j = 0; j < matrix[0].length; j++) {
+                matrix[rowIndex][j] += 1;
+            }
+        }
+    }
+}

src/test/java/com/fishercoder/_1252Test.java

@@ -0,0 +1,36 @@
+package com.fishercoder;
+
+import com.fishercoder.solutions._1252;
+import org.junit.BeforeClass;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+public class _1252Test {
+    private static _1252.Solution1 solution1;
+    private static int[][] indices;
+
+    @BeforeClass
+    public static void setup() {
+        solution1 = new _1252.Solution1();
+    }
+
+    @Test
+    public void test1() {
+        indices = new int[][]{
+                {0, 1},
+                {1, 1}
+        };
+        assertEquals(6, solution1.oddCells(2, 3, indices));
+    }
+
+    @Test
+    public void test2() {
+        indices = new int[][]{
+                {1, 1},
+                {0, 0}
+        };
+        assertEquals(0, solution1.oddCells(2, 2, indices));
+    }
+
+}