Compilare: main.cpp: In function 'int main()': main.cpp:44:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i = 0; i < p.size(), n != 1, p[i] * p[i] <= n; i++) { ~~^~~~~~~~~~ main.cpp:44:21: warning: value computed is not used [-Wunused-value] main.cpp:44:35: warning: right operand of comma operator has no effect [-Wunused-value] for (int i = 0; i < p.size(), n != 1, p[i] * p[i] <= n; i++) { ~~^~~~