function Main(INPUT){
  const input = INPUT.split("\n");
  const [N,S,B]=input[0].split(" ").map(_=>parseInt(_));
  let h=0;
  const H=input[1].split(" ").map(_=>parseInt(_));
  h=H[0]+S*B;
  for(let i=1;i<N;i++){
    if(H[i]>h){
      console.log("No");
      return;
    }
    h=Math.max(h, H[i]+S*B);
  }
  console.log("Yes");
}
Main(require("fs").readFileSync("/dev/stdin", "utf8"));