How to constantly update and print a 2d array? - c++

Question

So I'm currently working on a small project named dungeon crawl, where the user controls a char, player, and tries to reach another char, treasure. So far I have been able to program this but every time I print the board, it prints another game board right below the previous one! I want the board to constantly update the position of the player, not move the player and then print out a whole new board! I know this is a logic error but I cannot seem to find an answer, thanks in advance guys:
class Player
{
public:
int posX = 5;
int posY = 10;
char avatar = 'G';
};
class Treasure
{
public:
int posX = 2;
int posY = 10;
char avatar = 'X';
};
char board[10][20];
char player_move = 0;
bool player_win = 0;
Player p;
Treasure t;
void fill_board()
{
for (int i = 0; i < 10; ++i)
{
for (int j = 0; j < 20; ++j)
board[i][j] = '.';
}
}
void print_board()
{
for (int i = 0; i < 10; ++i)
{
for (int j = 0; j < 20; ++j)
{
cout << board[i][j];
}
cout << endl;
}
}
void set_player()
{
board[p.posX][p.posY] = p.avatar;
}
void erase_board(char b[][20])
{
for (int i = 0; i < 20; ++i)
{
for (int j = 0; j < 40; ++j)
board[i][j] = 0;
}
}
int main()
{
// Make board
fill_board();
// Set initial player position
board[p.posX][p.posY] = p.avatar;
// Set treasure position
board[t.posX][t.posY] = t.avatar;
// Start of game
player_win = false;
cout << "Welcome to dungeon crawl! To move press 'w', 'a', 's' , 'd' " << endl;
cout << endl;
//Prints board
print_board();
//Player movement
while (player_win == false)
{
cin >> player_move;
switch (player_move)
{
case 'w':
board[p.posX][p.posY] = '.';
p.posX -= 1;
break;
case 's':
board[p.posX][p.posY] = '.';
p.posX += 1;
break;
case 'a':
board[p.posX][p.posY] = '.';
p.posY -= 1;
break;
case 'd':
board[p.posX][p.posY] = '.';
p.posY += 1;
break;
}
set_player();
print_board();
// Check if player has won
if (p.posX == t.posX && p.posY == t.posY)
player_win = true;
}
cout << "\nCongratulations you win!!" << endl;
return 0;
}