Compilare: main.cpp: In function 'int get_number(int&)': main.cpp:35:9: warning: statement has no effect [-Wunused-value] for(start; start<p; start++) ^~~~~ main.cpp: In function 'int solve_paranthesis(int)': main.cpp:55:10: warning: statement has no effect [-Wunused-value] for(i; to_solve[i]!=')'&&i<to_solve.length(); i++) ^ main.cpp:55:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(i; to_solve[i]!=')'&&i<to_solve.length(); i++) ~^~~~~~~~~~~~~~~~~~