Compilare: main.cpp: In function 'int main()': main.cpp:29:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < p[i].size(); ++j) ~~^~~~~~~~~~~~~ main.cpp:64:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < p[i - 1].size(); ++j) ~~^~~~~~~~~~~~~~~~~