function main(input) {
  const prams = input.split('\n');
  const demon = prams[0].split(' ');
  const player = prams[1].split(' ');
  const demonSpeed = demon[1] * 1;
  const playerSpeed = player[1] * 1;
  var demonPosition = demon[0] * 1;
  var playerPosition = player[0] * 1;
  var distance = demonPosition - playerPosition;
  var isCatched = 'NO';
  if (distance < 0) {
    distance = distance * -1;
  }
  for (var i = 0;i < prams[2];i++) {
    if (demonPosition > playerPosition) {
      demonPosition -= demonSpeed;
      playerPosition -= playerSpeed;
    } else {
      demonPosition += demonSpeed;
      playerPosition += playerSpeed;
    }
    for (var j = 0;j < demonSpeed;j++) {
      distance = demonPosition - j - playerPosition;
      if (distance < 0) {
        distance = distance * -1;
      }
      if (distance === 0) {
        isCatched = 'YES';
      }
    }
  }
  console.log(isCatched);
}
main(require('fs').readFileSync('/dev/stdin', 'utf8'));