feat(string): Add 1408

KMP should be used for optimization..
euchangxian · Jan 9, 2025 · 703f8a7 · 703f8a7
1 parent 6008e38
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diff --git a/C++/1408-StringMatchingInAnArray/Solution.cpp b/C++/1408-StringMatchingInAnArray/Solution.cpp
@@ -0,0 +1,33 @@
+#include <cstddef>
+#include <cstdlib>
+#include <string>
+#include <string_view>
+#include <vector>
+
+class Solution {
+ public:
+  std::vector<std::string> stringMatching(std::vector<std::string>& words) {
+    // Return all words that is a substring of another word.
+    // Naively, O(n^2 * L^2), compare each string with every other string in
+    // O(L^2) time.
+    // Can we do better?
+    // KMP... instead of naive string matching.
+    std::vector<std::string> result;
+    result.reserve(words.size());
+    for (int i = 0; i < words.size(); ++i) {
+      for (int j = 0; j < words.size(); ++j) {
+        if (i == j) {
+          continue;
+        }
+
+        std::string_view curr{words[i]};
+        std::string_view next{words[j]};
+        if (next.contains(curr)) {
+          result.emplace_back(words[i]);
+          break;  // Only want to push this word once.
+        }
+      }
+    }
+    return result;
+  }
+};
diff --git a/README.md b/README.md
@@ -382,6 +382,7 @@ Now solving in C++. Like it.
 | 1395 | CountNumberOfTeams                                               |                                                  [![C++](assets/c++.svg)](C++/1395-CountNumberOfTeams/Solution.cpp)                                                   |
 | 1404 | NumberOfStepsToReduceANumberInBinaryRepresentationToOne          |                                [![C++](assets/c++.svg)](C++/1404-NumberOfStepsToReduceANumberInBinaryRepresentationToOne/Solution.cpp)                                |
 | 1405 | LongestHappyString                                               |                                                  [![C++](assets/c++.svg)](C++/1405-LongestHappyString/Solution.cpp)                                                   |
+| 1408 | StringMatchingInAnArray                                          |                                                [![C++](assets/c++.svg)](C++/1408-StringMatchingInAnArray/Solution.cpp)                                                |
 | 1422 | MaximumScoreAfterSplittingAString                                |                                           [![C++](assets/c++.svg)](C++/1422-MaximumScoreAfterSplittingAString/Solution.cpp)                                           |
 | 1423 | MaximumPointsYouCanObtainFromCards                               |                                          [![C++](assets/c++.svg)](C++/1423-MaximumPointsYouCanObtainFromCards/Solution.cpp)                                           |
 | 1427 | PerformStringShifts                                              |                                                  [![C++](assets/c++.svg)](C++/1427-PerformStringShifts/Solution.cpp)                                                  |