solve set matrix zeros

Author: sora0319

set-matrix-zeroes/sora0319.java

@@ -0,0 +1,51 @@
+class Solution {
+    public void setZeroes(int[][] matrix) {
+        int M = matrix.length;
+        int N = matrix[0].length;
+
+        boolean firstRow = false;
+        boolean firstCol = false;
+
+        for(int i = 0; i < M; i++){
+            if(matrix[i][0] == 0){
+                firstRow = true;
+                break;
+            }
+        }
+
+        for(int j = 0; j < N; j++){
+            if(matrix[0][j] == 0){
+                firstCol = true;
+                break;
+            }
+        }
+
+        for(int i = 0; i < M; i++){
+            for(int j = 0; j < N; j++){
+                if(matrix[i][j] == 0){
+                    matrix[i][0] = 0;
+                    matrix[0][j] = 0;
+                }
+            }
+        }
+
+        for(int i = 1; i < M; i++){
+            for(int j = 1; j < N; j++){
+                if(matrix[i][0] == 0 || matrix[0][j] == 0) matrix[i][j] = 0;
+            }
+        }
+
+        if(firstRow){
+            for(int i = 0; i < M; i++){
+                matrix[i][0] = 0;
+            }
+        }
+
+        if(firstCol){
+            for(int j = 0; j < N; j++){
+                matrix[0][j] = 0;
+            }
+        }
+    }
+}
+