Compilare: main.cpp: In function 'int main()': main.cpp:30:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] main.cpp:31:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] main.cpp:33:20: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] main.cpp:34:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] main.cpp:36:24: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] main.cpp:37:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]