const reader = require("readline").createInterface({
  input: process.stdin,
  output: process.stdout,
});

let lines = [];
reader.on("line", (line) => {
  lines.push(line);
});

reader.on("close", () => {
  if (lines[0] === lines[1]) {
    console.log(lines[0]);
  } else {
    console.log(lines[2]);
  }
});