Compilare: user.cpp: In function ‘int main()’: user.cpp:22:36: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 0; i <= s.length() ; ++i ) ^ user.cpp:26:16: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if ( s[i] != ')' && s[i] != '(' && s[i] != ',') ^ user.cpp:38:16: warning: suggest explicit braces to avoid ambiguous ‘else’ [-Wparentheses] if ( s[i] != ')' && s[i] != '(' && s[i] != ',') ^ user.cpp:59:45: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int j = 1; j < V.size(); ++j ) ^ user.cpp:78:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 0; i < V2.size(); ++i ) ^ user.cpp:79:26: warning: NULL used in arithmetic [-Wpointer-arith] if ( V2[i][0] == NULL) ^ user.cpp:82:34: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( int i = 0; i < V2.size(); ++i ) ^ user.cpp:84:28: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ( i < V2.size()-1) ^ user.cpp:86:30: warning: NULL used in arithmetic [-Wpointer-arith] if ( V2[i][0] != NULL ) ^