int activeRow = 0;

void setBeat(int row, int index, int sample) {
  samples[row][index] = sample;
}


void keyPressed() {
  if(keyCode >= 49 && keyCode < 53) {
    activeRow = keyCode-49;
  } else {
    int sample = keyCode-65;
    println(sample);
    if(sample >= 0 && sample < numsounds) {
      setBeat(activeRow, beat, sample);
    }
  }
}