#include <bits/stdc++.h>
using namespace std;
 
// Helper function to check if 'sub' is a subsequence of 'x'
bool isSubsequence(const string &x, const string &sub) {
    int i = 0, j = 0;
    while (i < x.size() && j < sub.size()) {
        if (x[i] == sub[j]) j++;
        i++;
    }
    return j == sub.size();
}
 
int longestSubsequence(string x, string y) {
    int maxLen = 0;
    int n = y.size();
 
    // Generate all substrings of y
    for (int i = 0; i < n; i++) {
        string temp = "";
        for (int j = i; j < n; j++) {
            temp += y[j];
            if (isSubsequence(x, temp)) {
                maxLen = max(maxLen, j - i + 1);
            }
        }
    }
 
    return maxLen;
}
 
// Example usage
int main() {
    string x = "hackerranks";
    string y = "hackers";
    cout << longestSubsequence(x, y) << endl; // Output: 7
    return 0;
}
 

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