题解 | #进制转换#

#include <bits/stdc++.h>
using namespace std;

int main() {
    map<char, int> mp = { {'A', 10}, {'B', 11},{'C', 12}, {'D',13}, {'E',14},{'F', 15}};
    string str;
    while (cin >> str) {
        int num = 0;
        reverse(str.begin(), str.end());
        for (int i = 0; i < str.size() - 2; i++) {
            int x = mp.count(str[i]) > 0 ? mp[str[i]] : (str[i] - '0');
            num += x * pow(16, i);
        }
        cout << num << endl;
    }
    return 0;
}