// Find the number of characters in a string
function charCount(str) {
  let result = {};
  for(let char of str) {
    if(/[a-z0-9]/.test(char)) { // includes only lowercase a,b....z and 0,1....9
      result[char] ? result[char]++ : result[char] = 1;
    }
  }
  return result;
}

// Find whether the two strings are of anagram
function anagram(strOne, strTwo) {
  if(strOne.length != strTwo.length) {
    return false;
  }

  let populatedStrOne = {};
  for(let char of strOne) {
    populatedStrOne[char] = (populatedStrOne[char] || 0) + 1;
  }

  for(let char of strTwo) {
    if(!populatedStrOne[char]) {
     return false;
    } else {
      populatedStrOne[char] -= 1;
    }
  }

  return true;
}

// Find the coordinates in the given array
function sumZero(coordinates) {
 let result = [];
 for(let i = 0; i < coordinates.length; i++) {
   for(let j = i + 1; j < coordinates.length; j++) {
     if(coordinates[i] + coordinates[j] == 0) {
       result.push(`${coordinates[i]}, ${coordinates[j]}`);
     }
   }
 }

 return result;
}

// Find the unique values in the given array
function countUniqueValues(arr) {
  let populatedObj = {};
  let result = [];

  for(let el of arr) {
    populatedObj[el] = (populatedObj[el] || 0) + 1;
  }

  for(let key in populatedObj) {
    if(populatedObj[key] == 1) {
      result.push(key);
    }
  }

  return result;
}

/* Searching Algorithms
* LinearSearch
* BinarySearch
*/

// Linear Search
function LinearSearch(arr, num) {
 for(let i = 0; i < arr.length; i++) {
  if(arr[i] == num) {
    return i;
  }
 }
 return -1;
}

// Binary Search
function BinarySearch(arr, num) {
  let start = 0;
  let end = arr.length - 1;
  let middle = Math.floor((start + end) / 2);

  while(num != arr[middle] && start <= end) {
    if(num > arr[middle]) {
      start = middle + 1;
    } else {
      end = middle - 1;
    }

    middle = Math.floor((start + end) / 2);
  }

  return arr[middle] == num ? middle : -1;
}

/* Sorting
* BubbleSort
*/

// BubbleSort
function BubbleSort(arr) {
  for(let i = 0; i < arr.length; i++) {
    for(let j = i + 1; j < arr.length; j++) {
      if(arr[i] > arr[j]) {
        let temp = arr[i];
        arr[i] = arr[j];
        arr[j] = temp;
      }
    }
  }

  return arr;
}

// OptmisedBubbleSort
function OptimisedBubbleSort(arr) {
  let noSwaps;
  for(let i = 0; i < arr.length; i++) {
    noSwaps = true
    for(let j = i + 1; j < arr.length; j++) {
      if(arr[i] > arr[j]) {
        let temp = arr[i];
        arr[i] = arr[j];
        arr[j] = temp;
        noSwaps = false;
      }
    }
    if(noSwaps) break;
  }

  return arr;
}