LCS (Longest Common Subsequence)

LCS/README.md

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+LCS (Longest Common Subsequence)
+
+See https://en.wikipedia.org/wiki/Longest_common_subsequence_problem

LCS/example.cpp

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+#include <iostream>
+#include <string>
+
+extern int lcs(const std::string&, const std::string&);
+
+int main()
+{
+    std::string s1 = "Tsuki ga kirei desu ne";
+    std::string s2 = "Taiyo ga mabushii desu ne";
+    std::cout << lcs(s1, s2) << std::endl;
+}

LCS/lcs.cpp

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+#include <string>
+#include <vector>
+
+int lcs(const std::string& A, const std::string& B)
+{
+    std::vector<std::vector<int>> LCS(A.length() + 1);        
+    for (unsigned int i = 0; i < LCS.size(); i++)
+        LCS[i].resize(B.length() + 1);
+
+    for (unsigned int i = 1; i <= A.length(); i++) {
+        for (unsigned int j = 1; j <= B.length(); j++) {
+            if (A[i - 1] == B[j - 1]) {
+                LCS[i][j] = LCS[i - 1][j - 1] + 1;
+            }
+            else {
+                LCS[i][j] = std::max(LCS[i - 1][j], LCS[i][j - 1])
+            }
+        }
+    }
+    return LCS[A.length()][B.length()];
+}