Compilare: main.cpp: In function 'void precal()': main.cpp:21:19: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 2; i < le; i++){ ~~^~~~ main.cpp:25:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int j = i+i, m = 1; j < le; j += i, m++){ ~~^~~~ main.cpp: In function 'lint recur(lint)': main.cpp:50:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 2; i <= n; i++){ ~~^~~~