sort a vector of vectors in c++ by size of each vector [duplicate]

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Sorting a vector of custom objects

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Answers

You just need to specify a predicate:

vector<vector<int>> vecs;

vecs.push_back(vector<int>(4));

vecs.push_back(vector<int>(2));

vecs.push_back(vector<int>(1));

vecs.push_back(vector<int>(3));



std::sort(vecs.begin(), vecs.end(), [](const vector<int> & a, const vector<int> & b){ return a.size() < b.size(); });

This code sorts the vectors by smallest to largest.