我用了一个文件读写操作，就是只写不读，然后文件读写操作完了之后，我重定向到了控制台输入，然后用了system("cls"),但是却显示一堆方框，如下图
请问有什么好的解决方法吗？ 完整代码

#include<bits/stdc++.h>
#include<windows.h>
using namespace std;
std::string userinput[3005];
int main(){
	for(int i=1;i<=25;i++)std::cout<<'\n';
	for(int i=1;i<=75;i++)std::cout<<' ';
	std::cout<<"write your code!"; 
	//_sleep(5000);
	system("cls");
	for(int i=1;i<=15;i++)std::cout<<'\n';
	for(int i=1;i<=70;i++)std::cout<<" ";
	std::cout<<"stop = Close the program."<<'\n';
	for(int i=1;i<=70;i++)std::cout<<" ";
	std::cout<<"save = Save the code."<<'\n';
	for(int i=1;i<=70;i++)std::cout<<" ";
	std::cout<<"run = runing."<<'\n';
	for(int i=1;i<=70;i++)std::cout<<" ";
	std::cout<<"test = Test that the code is saved in its entirety."<<'\n';
	std::cout<<'\n'<<'\n'<<'\n'<<'\n'<<'\n'<<'\n'<<'\n'<<"Your Code:"<<'\n';
	string str;
	int idx=0;
	while(1){
		//system("cls");
		idx++;
		getline(std::cin,str);
		userinput[idx]=str; 
		if(str=="stop"){
			std::cout<<"IDE is closed."<<'\n';
			return 0;
		}
		if(str=="save"){
			freopen("test2.cpp","w",stdout);
			for(int i=1;i<=idx-1;i++){
				std::cout<<userinput[i]<<'\n';
			}
			fclose(stdout);
			freopen("CON","r",stdout);
			freopen("CON","w",stdout);
			std::cout<<"The save was successful.";;
			_sleep(5000);
			//std::cout<<"\033[2J";
			system("cls");
			for(int i=1;i<=15;i++)std::cout<<'\n';
			for(int i=1;i<=70;i++)std::cout<<" ";
			std::cout<<"stop = Close the program."<<'\n';
			for(int i=1;i<=70;i++)std::cout<<" ";
			std::cout<<"save = Save the code."<<'\n';
			for(int i=1;i<=70;i++)std::cout<<" ";
			std::cout<<"run = runing."<<'\n';
			for(int i=1;i<=70;i++)std::cout<<" ";
			std::cout<<"test = Test that the code is saved in its entirety."<<'\n';
			std::cout<<'\n'<<'\n'<<'\n'<<'\n'<<'\n'<<'\n'<<'\n'<<"Your Code:"<<'\n';
		}
	}
}