Compilare: main.cpp: In function 'void p1()': main.cpp:37:35: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = pr.size() - 1; i >= pr.size() - m; --i) { ~~^~~~~~~~~~~~~~~~ main.cpp: In function 'void p2()': main.cpp:65:23: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < pr.size(); ++i) { ~~^~~~~~~~~~~ main.cpp:80:27: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = 0; j < comb.size(); ++j) { ~~^~~~~~~~~~~~~ main.cpp:93:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int j = v.size() - 1; j >= v.size() - m; --j) { ~~^~~~~~~~~~~~~~~