leetcode-solutions/combinations.cpp at master · avidLearnerInProgress/leetcode-solutions · GitHub

22 lines (21 loc) · 621 Bytes

class Solution {

public:

vector<vector<int>> combine(int n, int k) {

vector<vector<int>> output;

vector<int> combination;

combine(output, combination, n, k, 1);

return output;

}

private:

void combine(vector<vector<int>>& output, vector<int> combination, int n, int k, int i) {

if (combination.size() == k) {

output.push_back(combination);

return;

}

for (int j = i; j <= n; j++) {

combination.push_back(j);

combine(output, combination, n, k, j + 1);

combination.pop_back();

}

};

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