Compilare: user.cpp: In function ‘int main()’: user.cpp:20:30: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( ; i < strlen(c) ; i ++ ) ^ user.cpp:21:55: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if(c[i]>c[i+1]&&c[i+1]<c[i+2]&&i+2<strlen(c)) ^ user.cpp:23:64: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(c[j]>c[j+1]&&c[j+1]<c[j+2]&&j+2<strlen(c)) ^ user.cpp:39:38: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for ( i = 2 ; i < strlen(c) ; i ++ ) ^