Compilare: user.cpp: In function ‘int main()’: user.cpp:18:33: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=1;i<strlen(s)-1;i++) ^ user.cpp:23:29: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] while(j<strlen(s) && s[j-1]>s[j] && s[j]<s[j+1]) ^ user.cpp:37:31: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i=0;i<strlen(s);i++) ^