const input = require('fs').readFileSync('/dev/stdin', 'utf8');
const H = input.split('\n').map(v => Number(v));
const arr = [
  {
    name: 'A',
    value: H[0]
  },
  {
    name: 'B',
    value: H[1]
  },
  {
    name: 'C',
    value: H[2]
  },
];
arr.sort((a, b) => a.value - b.value).reverse();
console.log(arr.map(v => v.name).join('\n'));