Compilare: user.cpp: In function ‘int main()’: user.cpp:18:26: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] for (int i=0; i<s.size(); i++) { ^ user.cpp:19:18: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (s[i]>='a' && s[i]<='z' || s[i]>='A' && s[i]<='Z') { ^ user.cpp:24:53: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] } else if (s[i]=='!' || s[i]=='?' || (i<s.size()-2) && s[i]=='.' && s[i+1]=='.' && s[i+2]=='.') { ^ user.cpp:24:84: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] } else if (s[i]=='!' || s[i]=='?' || (i<s.size()-2) && s[i]=='.' && s[i+1]=='.' && s[i+2]=='.') { ^ user.cpp:30:21: warning: comparison between signed and unsigned integer expressions [-Wsign-compare] if ((i<s.size()-2) && s[i]=='.' && s[i+1]=='.' && s[i+2]=='.') i+=2; ^