Compilare: user.cpp: In function ‘int main()’: user.cpp:26:31: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (v[d].val=='{' && s[i]=='}' || v[d].val=='[' && s[i]==']' || v[d].val=='(' && s[i]==')') ^ user.cpp:26:91: warning: suggest parentheses around ‘&&’ within ‘||’ [-Wparentheses] if (v[d].val=='{' && s[i]=='}' || v[d].val=='[' && s[i]==']' || v[d].val=='(' && s[i]==')') ^