Java(javac 1.8) 解法, 执行用时: 52ms, 内存消耗: 12368K, 提交时间: 2020-08-05 10:05:40

import java.util.*;

public class Main {
    public static int[] getNumbers(int n,String[][] words){
        int[] ans = new int[26];

        for(int i=0;i<n;i++){
            int[] a1 = new int[26];
            int[] a2 = new int[26];

            for(char c:words[i][0].toCharArray()){
                a1[c-'a']++;
            }
            for(char c:words[i][1].toCharArray()){
                a2[c-'a']++;
            }
            for(int j=0;j<26;j++){
                ans[j] += Math.max(a1[j],a2[j]);
            }
        }

        return ans;
    }


    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n=sc.nextInt();
        String[][] words = new String[n][2];

        for (int i = 0; i < n; i++) {
            words[i][0] = sc.next();
            words[i][1] = sc.next();
        }

        int[] ans = getNumbers(n,words);
        for(int i=0;i<26;i++) System.out.println(ans[i]);

        sc.close();
    }
}

C++14(g++5.4) 解法, 执行用时: 4ms, 内存消耗: 404K, 提交时间: 2020-08-06 13:36:01

#include <bits/stdc++.h>
using namespace std;
#define ll long long
const int maxn=4e5+7;
const int INF=0x3f3f3f3f;
const int T=1e4+1;
map<char,int>op;
map<char,int>M;
map<char,int>N;
int  main()
{
  int n;
  cin>>n;
  for (int i=1;i<=2*n;++i)
  {
      string s;
      cin>>s;
      for(int j=0;j<s.size();++j)
      {
          if (s[j]>='a'&&s[j]<='z')
          {
              if (i%2==1)++M[s[j]];
              if (i%2==0)++N[s[j]];
          }
      }
      if (i%2==0)for (char i='a';i<='z';++i)op[i]+=max(M[i],N[i]);
      if(i%2==0){M.clear();N.clear();}
  }
  for (int i=0;i<26;++i)
  {
      cout<<op[char(i+'a')]<<endl;
  }
  return 0;
}

C++11(clang++ 3.9) 解法, 执行用时: 3ms, 内存消耗: 504K, 提交时间: 2020-08-05 14:58:58

#include<bits/stdc++.h>
#pragma GCC optimize(2)
using namespace std;
typedef long long ll;
const int N=50005;
int cnt[30];
int main(){
	std::ios::sync_with_stdio(false);cin.tie(0), cout.tie(0);
	int n,a[30];
	cin>>n;
	string str;
	for(int i=0;i<n;i++){
		memset(a,0,sizeof(a));
		cin>>str;
		for(auto j:str){
			a[j-'a']++;
			cnt[j-'a']++;
		}
		str.clear();
		cin>>str;
		for(auto j:str){
			if(a[j-'a']) a[j-'a']--;
			else cnt[j-'a']++;
		}
	}
	for(int i=0;i<26;i++){
		cout<<cnt[i]<<endl;
	}
	return 0;
}