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// Time Complexity : O(N)
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// Space Complexity : O(1)
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var summaryRanges = function (nums) {
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  // Create a list of string to store the output result...
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  const output = [];
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  // Start traversing the array from idx = 0 till idx < sizeofarray in a while loop.
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  let idx = 0;
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  while (idx < nums.length) {
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    // Initialize beg and last index for identifying the continuous element in the array...
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    let beg, last;
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    // Mark the number at current index as beginning element of the range...
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    beg = nums[idx];
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    // Traverse the array beggining from current index & find the last element whose difference from previous element is exactly 1, i.e. nums[idx + 1] == nums[idx] + 1...
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    while (idx + 1 < nums.length && nums[idx + 1] == nums[idx] + 1) idx++;
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    // Set this element as last element of the range...
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    last = nums[idx];
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    // If continuous element isn't present...
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    if (beg == last) output.push(beg + "");
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    // If present...
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    else output.push(beg + "->" + last);
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    idx++;
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  }
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  return output; // Return the output result list...
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};