Compilare: user.cpp: In function ‘int ut(int, int, int)’: user.cpp:43:50: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(isdigit(s[a][b][i+2])&&i+2<s[a][b].length()){ ^ user.cpp: In function ‘void kitolt(int, int)’: user.cpp:54:42: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<s[a][b].length();i++){ ^ user.cpp:69:46: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<s[a][b].length();i++){ ^