三刷74

Author: diguage

docs/0074-search-a-2d-matrix.adoc

@@ -62,6 +62,15 @@ include::{sourcedir}/_0074_SearchA2DMatrix.java[tag=answer]
 include::{sourcedir}/_0074_SearchA2DMatrix_2.java[tag=answer]
 ----
 --
+
+三刷::
++
+--
+[{java_src_attr}]
+----
+include::{sourcedir}/_0074_SearchA2DMatrix_3.java[tag=answer]
+----
+--
 ====
 
 

src/main/java/com/diguage/algo/leetcode/_0074_SearchA2DMatrix_2.java

@@ -7,16 +7,18 @@ public class _0074_SearchA2DMatrix_2 {
    * @since 2025-11-18 22:23:27
    */
   public boolean searchMatrix(int[][] matrix, int target) {
-    int m = matrix.length;
-    int n = matrix[0].length;
-    int low = 0, high = m * n - 1;
+    int row = matrix.length;
+    int column = matrix[0].length;
+    int low = 0, high = row * column - 1;
     while (low <= high) {
       int mid = low + (high - low) / 2;
-      int row = mid / n;
-      int col = mid % n;
-      if (matrix[row][col] == target) {
+      int r = mid / column;
+      int c = mid % column;
+      int num = matrix[r][c];
+      if (num == target) {
         return true;
-      } else if (matrix[row][col] < target) {
+      }
+      if (num < target) {
         low = mid + 1;
       } else {
         high = mid - 1;

src/main/java/com/diguage/algo/leetcode/_0074_SearchA2DMatrix_3.java

@@ -0,0 +1,35 @@
+package com.diguage.algo.leetcode;
+
+public class _0074_SearchA2DMatrix_3 {
+  // tag::answer[]
+
+  /**
+   * @author D瓜哥 · https://www.diguage.com
+   * @since 2025-11-18 22:23:27
+   */
+  public boolean searchMatrix(int[][] matrix, int target) {
+    int r = 0, c = matrix[r].length - 1;
+    while (r < matrix.length && 0 <= c) {
+      int num = matrix[r][c];
+      if (num == target) {
+        return true;
+      }
+      if (target < num) {
+        c--;
+      } else {
+        r++;
+      }
+    }
+    return false;
+  }
+  // end::answer[]
+
+  static void main() {
+    new _0074_SearchA2DMatrix_3()
+      .searchMatrix(new int[][]{
+          {1, 3, 5, 7},
+          {10, 11, 16, 20},
+          {23, 30, 34, 60}},
+        3);
+  }
+}