#include using namespa

#include using namespace std;int lps(string seq, int i, int j) { \tint len1, len2;\tif (i == j) \t\treturn 1;\tif (i > j) \t\treturn 0;\tif (seq[i] == seq[j])\t\treturn lps(seq, i   1, j - 1)   2; \tlen1 = lps(seq, i, j - 1);\tlen2 = lps(seq, i   1, j); \tif (len1 > len2)\t\treturn len1; \treturn len2;}int main() {\tstring seq = "acmerandacm"; \tint n = seq.size();\tcout << lps(seq, 0, n - 1) << endl; \treturn 0;}

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