function largestNonAdjacentSum(numbers: number[]): number {
  
  if ( numbers.length === 0 )return 0;
  if ( numbers.length === 1) return numbers[0]
  
  const hasNegatives = numbers.some(n => n < 0);
  if (hasNegatives) return 0;
  
  let maxSum = 0;
  let currentSum = 0;

  for(let i = 0; i < numbers.length; i ++ ){ 
    const newMax = Math.max(maxSum, currentSum + numbers[i]);
    currentSum = maxSum;
    maxSum = newMax
  }


  return maxSum
}

// No modificar: necesario para evaluar el resultado.
export { largestNonAdjacentSum };