各位大佬是不是因为getline的问题呢？

#include<iostream>
#include <cmath>
#include<string>
#include<sstream>
#include<stack>
#include<vector>
#include<map>
#include<queue>
using namespace std;
int arr[26];
bool isEmpty() {
	for (int i = 0; i < 26; ++i) {
		if (arr[i] != 0)return false;
	}
	return true;
}
int main() {
	stack<string> output;
	output.push("A B C D E F G H I J K L M N O P Q R S T U V W X Y Z");
	string s1, s2, s3, s4;
	getline(cin, s1);
	getline(cin, s2);
	getline(cin, s3);
	getline(cin, s4);
	for (int i = 0; i < s1.length();++i) {
		arr[(int)s1[i] - 65]++;
	}
	for (int i = 0; i < s2.length();++i) {
		arr[(int)s2[i] - 65]++;
	}
	for (int i = 0; i < s3.length();++i) {
		arr[(int)s3[i] - 65]++;
	}
	for (int i = 0; i < s4.length();++i) {
		arr[(int)s4[i] - 65]++;
	}
	while (!isEmpty()) {
		string line = "";
		for (int i = 0; i < 26; ++i) {
			if (arr[i] == 0) {
				line += "  ";
			}
			else {
				line += "* ";
				arr[i]--;
			}
		}
		output.push(line);
	}
	while (!output.empty()) {
		string line = output.top();
		cout << line << endl;;
		output.pop();
	}
	
}