Compilare: main.cpp: In function 'int main()': main.cpp:92:25: warning: format '%d' expects argument of type 'int', but argument 3 has type 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wformat=] 92 | fprintf(fout, "%d ", v[i].size()); | ~^ ~~~~~~~~~~~ | | | | int std::vector<int>::size_type {aka long unsigned int} | %ld main.cpp:94:26: warning: comparison of integer expressions of different signedness: 'int' and 'std::vector<int>::size_type' {aka 'long unsigned int'} [-Wsign-compare] 94 | for(int j = 0; j < v[i].size(); j++) | ~~^~~~~~~~~~~~~