Create set-matrix-zeroes.cpp

Author: kamyu104

C++/set-matrix-zeroes.cpp

@@ -0,0 +1,50 @@
+// Time:  O(m * n)
+// Space: O(1)
+
+class Solution {
+public:
+    void setZeroes(vector<vector<int>>& matrix) {
+        if (matrix.empty()) {
+            return;
+        }
+
+        bool has_zero = false;
+        int zero_i = -1, zero_j = -1;
+
+        for (int i = 0; i < matrix.size(); ++i) {
+            for (int j = 0; j < matrix[0].size(); ++j) {
+                if (matrix[i][j] == 0) {
+                    if (!has_zero) {
+                        zero_i = i;
+                        zero_j = j;
+                        has_zero = true;
+                    }
+                    matrix[zero_i][j] = 0;
+                    matrix[i][zero_j] = 0;
+                }
+            }
+        }
+
+        if (has_zero) {
+            for (int i = 0; i < matrix.size(); ++i) {
+                if (i == zero_i) {
+                    continue;
+                }
+                for (int j = 0; j < matrix[0].size(); ++j) {
+                    if (j == zero_j) {
+                        continue;
+                    }
+                    if (matrix[zero_i][j] == 0 || matrix[i][zero_j] == 0) {
+                        matrix[i][j] = 0;
+                    }
+                }
+            }
+            for (int i = 0; i < matrix.size(); ++i) {
+                matrix[i][zero_j] = 0;
+            }
+            for (int j = 0; j < matrix[0].size(); ++j) {
+                matrix[zero_i][j] = 0;
+            }
+        }
+    }
+};