Add C++ implemention

Signed-off-by: begeekmyfriend <[email protected]>

Author: begeekmyfriend

1143_longest_common_subsequence/Makefile

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+all:
+	gcc -O1 -o test lcs.c

1143_longest_common_subsequence/lcs.c

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+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+
+
+static int max(int a, int b)
+{
+    return a > b ? a : b;
+}
+
+int longestCommonSubsequence(char * text1, char * text2)
+{
+    int i, j;
+    int l1 = strlen(text1);
+    int l2 = strlen(text2);
+    int **dp = malloc((l1 + 1) * sizeof(int *));
+    for (i = 0; i < l1 + 1; i++) {
+        dp[i] = malloc((l2 + 1) * sizeof(int));
+    }
+    memset(dp[0], 0, (l2 + 1) * sizeof(int));
+    for (i = 1; i <= l1; i++) {
+        dp[i][0] = 0;
+    }
+    
+    for (i = 1; i <= l1; i++) {
+        for (j = 1; j <= l2; j++) {
+            if (text1[i - 1] == text2[j - 1]) {
+                dp[i][j] = dp[i - 1][j - 1] + 1;
+            } else {
+                dp[i][j] = max(dp[i - 1][j], dp[i][j - 1]);
+            }
+        }
+    }
+    return dp[l1][l2];
+}
+
+int main(int argc, char **argv)
+{
+    if (argc != 3) {
+        fprintf(stderr, "Usage: ./test s1 s2\n");
+        exit(-1);
+    }
+
+    printf("%d\n", longestCommonSubsequence(argv[1], argv[2]));
+    return 0;
+}

1143_longest_common_subsequence/lcs.cc

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+#include <bits/stdc++.h>
+
+using namespace std;
+
+class Solution {
+public:
+    int longestCommonSubsequence(string text1, string text2) {
+        int l1 = text1.length();
+        int l2 = text2.length();
+        vector<int> dp(l2 + 1);
+        int up = 0;
+        for (int i = 1; i <= l1; i++) {
+            int left_up = 0;
+            for (int j = 1; j <= l2; j++) {
+                up = dp[j];
+                if (text1[i - 1] == text2[j - 1]) {
+                    dp[j] = left_up + 1;
+                } else {
+                    dp[j] = max(up, dp[j - 1]);
+                }
+                left_up = up;
+            }
+        }
+        return dp[l2];
+    }
+};