Compilare: user.cpp: In function ‘int main()’: user.cpp:14:20: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(ch>='a' && ch<='z' || ch>='A' && ch<='Z' || ch>='0' && ch<='9') ^ user.cpp:14:64: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(ch>='a' && ch<='z' || ch>='A' && ch<='Z' || ch>='0' && ch<='9') ^ user.cpp:17:26: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(ch1>='a' && ch1<='z' || ch1>='A' && ch1<='Z' || ch1>='0' && ch1<='9') ^ user.cpp:17:74: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(ch1>='a' && ch1<='z' || ch1>='A' && ch1<='Z' || ch1>='0' && ch1<='9') ^ user.cpp:22:16: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(ch>='a' && ch<='z' || ch>='A' && ch<='Z' || ch>='0' && ch<='9') ^ user.cpp:22:60: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if(ch>='a' && ch<='z' || ch>='A' && ch<='Z' || ch>='0' && ch<='9') ^