String[] signature;
int index = 1;

void setup() {
  size(400, 400);
  background(255);
  stroke(0);
  strokeWeight(10);
  frameRate(100);
  signature = loadStrings("U10S1.TXT");
}

void draw() {
  if (index < signature.length) {
    String[] coordinates = split(signature[index], ' ');
    if (coordinates.length >= 2) {
      int x = int(coordinates[0]) / 20;
      int y = height - int(coordinates[1]) / 20;
      point(x, y);
    }
    index = index + 1;
  } else
    noLoop();
}