function Main(input) {
  input = input.trim()
  input = input.split(" ");
  if((input[0]>=input[2]&&input[2]>=input[1])||(input[0]<=input[2]&&input[2]<=input[1])) console.log("Yes");
  else console.log("No")
}Main(require("fs").readFileSync("/dev/stdin", "utf8"));
