题解 | 进制转换

#include <iostream>
#include <string>
using namespace std;
long long CharToLong(char x){
    if(x>='0'&&x<='9') return x-'0';
    else return x-'A'+10;
}
int main() {
    string a;
    while(cin>>a){
        long long sum=0;
        for(int i=2;i<a.size();i++){
            sum = sum*16 + CharToLong(a[i]);
            }
        cout<<sum<<endl;
    }
    return 0;
}