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const rules = [
  ['scissors', 'paper lizard'],
  ['paper', 'rock spock'],
  ['lizard', 'spock paper'],
  ['rock', 'lizard scissors'],
  ['spock', 'scissors rock']
];
const result = ['spock spock', 'scissors spock', 'lizard spock'].map(curr => {
  const value = curr.split(' ');
  if(value[0] === value[1]) { return 'empate'; }

  if(rules.find(r => r[0] === value[0] && r[1].includes(value[1]))) {
    return value[0];
  }

  if(rules.find(r => r[0] === value[1] && r[1].includes(value[0]))) {
    return value[1];
  }

});
console.log(result);