题解

没人发题解，我来发一个

#include<bits/stdc++.h>
using namespace std;
struct node{
	string code;
	int cnt;
};
bool cmp(node a,node b){
	if (a.cnt != b.cnt){
		return a.cnt > b.cnt;
	}
	return a.code < b.code;
}
int f(char c){
	if ('0' <= c and c <= '9'){
		return c - '0';
	}
	return c - 'A' + 10;
}
int g(string s){
	return f(s[0]) * 16 + f(s[1]);
}
vector<node> v;
int n;
map<string, int> mp;
vector<string> vs;
string s;
int h(string s){
	int ma = 2e9, k = 0;
	for (int i = 0;i < 16;i ++){
		int a = abs(g(v[i].code) - g(s));
		if (a < ma){
			ma = a;
			k = i;
		}
	}
	return k;
}
char p(int a){
	if (a < 10){
		return a + '0';
	}
	return a - 10 + 'A';
}
int main(){
	cin >> n;
	for (int i = 0;i < n;i ++){
		cin >> s;
		vs.push_back(s);
		for (int j = 0;j < s.length() / 2; j ++){
			mp[s.substr(j * 2, 2)]++;
		}
	}
	for (auto a: mp){
		v.push_back({a.first, a.second});
	}
	sort(v.begin(), v.end(), cmp);
	for (auto a: v){
		//cout << a.code << " " << a.cnt << endl;
	}
	for (int i = 0;i < 16;i ++){
		cout << v[i].code;
	}
	cout << endl;
	for (string s: vs){
		for (int j = 0;j < s.length() / 2; j ++){
			cout << p(h(s.substr(j * 2, 2)));
		}
		cout << endl;
	}
	return 0;
}