为什么我用了system("cls")之后输出就乱了

#include<bits/stdc++.h>
#include<windows.h>
#include<conio.h>
using namespace std;
#define random(a,b)  (rand()%(b-a+1)+a)
/*GetStdHandle(STD_OUTPUT_HANDLE)//句柄 
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED|FOREGROUND_GREEN|FOREGROUND_BLUE);//三色相加，白色
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED);//红色
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_GREEN);//绿色
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_BLUE);//蓝色
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED|FOREGROUND_GREEN);//红色和绿色相加，黄色
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED|FOREGROUND_BLUE);//红色和蓝色相加，粉色
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_GREEN|FOREGROUND_BLUE);//绿色和蓝色相加，青色
SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY);//没有添加颜色，原色*/
char tu[120][120];
int di=1,lo=1;
char tsc;
void ac(){
	SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED);
	cout<<"\n\n\n\n\n\t\t\t\t\t\t*欢迎来到“贪吃蛇”*";
	SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_GREEN|FOREGROUND_BLUE);
	cout<<"\n\t\t\t\t\t\t请选择难度 1.简单";
	SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED|FOREGROUND_GREEN);
	cout<<"\n\t\t\t\t\t\t\t   2.一般"; 
	SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED);
	cout<<"\n\t\t\t\t\t\t\t   3.难";
	SetConsoleTextAttribute(GetStdHandle(STD_OUTPUT_HANDLE),FOREGROUND_INTENSITY|FOREGROUND_RED|FOREGROUND_BLUE);
	cout<<"\n\t\t\t\t\t\t\t   4.魔鬼（建议不要来）";
	cin>>di;
//	system("cls");
	return ;
}
void dy(){
	for(int i=0 ; i<110 ; i++){
		tu[0][i]='-';
		tu[25][i]='-';
	}
	for(int i=1 ; i<25 ; i++){
		tu[i][0]='|';
		tu[i][20]='|';
		tu[i][109]='|';
	}
	string s="   Difficulty(难度)";
	string t="     Length(长度)";
	for(int i=3 ; i<19 ; i++){
		tu[3][i]=s[i]; 
	}
	for(int i=5 ; i<17 ; i++){
		tu[13][i]=t[i]; 
	}
	tu[4][10]=di+'0';
	tu[14][10]=lo+'0';
}
void out(){
	for(int i=0 ; i<26 ; i++){
		for(int j=0 ; j<110 ; j++){
			cout<<tu[i][j];
		}
		cout<<endl;
	}
}
int main(){
    dy();
    out();
	ac();
	out();
	return 0;
}

输出

--------------------------------------------------------------------------------------------------------------
|                   |                                                                                        |
|                   |                                                                                        |
|  Difficulty(难度) |                                                                                        |
|         1         |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|    Length(长度)   |                                                                                        |
|         1         |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
|                   |                                                                                        |
--------------------------------------------------------------------------------------------------------------





                                                *欢迎来到“贪吃蛇”*
                                                请选择难度 1.简单
                                                           2.一般
                                                           3.难
                                                           4.魔鬼（建议不要来）

--------------------------------------------------------------------------------------------------------------
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|Difficulty(难度)||
|1||
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|Length(长度)||
|1||
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--------------------------------------------------------------------------------------------------------------