var xPos = 0;
var yPos = 0;
# 0=right 1=down 2=left 3=up
var direction = 0;

while true {
    if direction == 0{
        var x = xPos + 1;
        xPos = x;
    }
    if direction == 1 {
        var y = yPos + 1;
        yPos = y;
    }
    if direction == 2{
        var x = xPos - 1;
        xPos = x;
    }
    if direction == 3 {
        var y = yPos - 1;
        yPos = y;
    }

    var input = readln();
    if input == "w" && direction != 1 {
      direction = 3;
    }
    if input == "a" && direction != 0 {
      direction = 2;
    }
    if input == "s" && direction != 3 {
      direction = 1;
    }
    if input == "d" && direction != 2 {
      direction = 0;
    }

    term_setpos(x, y);
    print("*");
}