如何判断车牌不在A，B，C，D，E，F，G，R，S，T之内？

for(int i = 0; i <n; i++) {
            cin>>a;
        if(a[0] =='A'||a[0] =='B'||a[0] =='C'||a[0] =='D'||a[0] =='E'||a[0] =='F'||a[0] =='G'||a[0] =='R'||a[0] =='S'||a[0] =='T') x++;
    }
 cout << n-x;

或者：

if(!(s[0]>='A'&&s[0]<='G'||s[0]>='R'&&s[0]<='T')) cnt++;