Compilare: user.cpp: In function ‘int main()’: user.cpp:13:12: warning: suggest parentheses around ‘+’ inside ‘>>’ [-Wparentheses] in >> s+1; ~^~ user.cpp:15:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < strlen(s); i++) ~~^~~~~~~~~~~ user.cpp:28:22: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for(int i = 1; i < strlen(s); i++) ~~^~~~~~~~~~~