feat(leetcode): add No.2946

Author: mickey0524

2946.matrix-similarity-after-cyclic-shifts.java

@@ -0,0 +1,42 @@
+// https://leetcode.com/problems/matrix-similarity-after-cyclic-shifts/description/
+// algorithms
+// Easy (56.67%)
+// Total Accepted: 17K
+// Total Submissions: 30K
+
+
+class Solution {
+
+    public boolean areSimilar(int[][] mat, int k) {
+        int m = mat.length;
+
+        if (m == 0) {
+            return false;
+        }
+
+        int n = mat[0].length;
+        k %= n;
+
+        for (int i = 0; i < m; i++) {
+            // 偶数往左，奇数往右
+            int direction = i & 1;
+            for (int j = 0; j < n; j++) {
+                int targetIdx;
+                if (direction == 0) {
+                    targetIdx = j - k;
+                    if (targetIdx < 0) {
+                        targetIdx += n;
+                    }
+                } else {
+                    targetIdx = (j + k) % n;
+                }
+                if (mat[i][j] != mat[i][targetIdx]) {
+                    return false;
+                }
+            }
+        }
+
+        return true;
+    }
+
+}