function twoSum(nums, target) {
    const numIndices = {}; // Create an object to store numbers and their indices
 
    for (let i = 0; i < nums.length; i++) {
        const complement = target - nums[i]; // Calculate the complement of the current number
 
        // Check if the complement is already in the object
        if (numIndices.hasOwnProperty(complement)) {
            // If it is, return the indices of the complement and the current number
            return [numIndices[complement], i];
        }
 
        // Otherwise, store the index of the current number in the object
        numIndices[nums[i]] = i;
    }
 
    // If no solution is found, return an empty array or throw an error
    return [];
}
 
// Example usage:
const nums = [2, 7, 11, 15];
const target = 9;
const result = twoSum(nums, target);
console.log(result); // Output: [0, 1]

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