Leetcode Algorithn

Today(3/30) Algorithm

1603. Design Parking System

Example 1:

Input
["ParkingSystem", "addCar", "addCar", "addCar", "addCar"][1, 1, 0], [1], [2], [3], [1]]
Output
[null, true, true, false, false]
Explanation
ParkingSystem parkingSystem = new ParkingSystem(1, 1, 0);
parkingSystem.addCar(1); // return true because there is 1 available slot for a big car
parkingSystem.addCar(2); // return true because there is 1 available slot for a medium car
parkingSystem.addCar(3); // return false because there is no available slot for a small car
parkingSystem.addCar(1); // return false because there is no available slot for a big car. It is already occupied.

code

var ParkingSystem = function(big,  medium, small) {
    bigCar = big;
    mediumCar = medium;
    smallCar = small;
};

/** 
 * @param {number} carType
 * @return {boolean}
 */
ParkingSystem.prototype.addCar = function(carType) {
    if(carType === 1 && bigCar){
        bigCar--
        return true;
    }
    
     if(carType === 2 && mediumCar){
        mediumCar--
        return true;
    }
    
     if(carType === 3 && smallCar){
        smallCar--
        return true;
    }
    return false
};

1512. Number of Good Pairs

Example 1:

Input: nums = [1,2,3,1,1,3]
Output: 4
Explanation: There are 4 good pairs (0,3), (0,4), (3,4), (2,5) 0-indexed.

Example 2:

Input: nums = [1,1,1,1]
Output: 6
Explanation: Each pair in the array are good.

Example 3:

Input: nums = [1,2,3]
Output: 0

code

var numIdenticalPairs = function(nums) {
  let numArr =[];
  
    for(let i =0; i< nums.length; i++){
      for (let j =1; j<nums.length; j++){
       if(i !== j && i < j){
          if(nums[i] === nums[j]) {
            numArr.push([i, j])
          }
        }
      }      
    }
    return numArr.length;
};

1365. How Many Numbers Are Smaller Than the Current Number

Example 1:

Input: nums = [8,1,2,2,3]
Output: [4,0,1,1,3]
Explanation:
For nums[0]=8 there exist four smaller numbers than it (1, 2, 2 and 3).
For nums[1]=1 does not exist any smaller number than it.
For nums[2]=2 there exist one smaller number than it (1).
For nums[3]=2 there exist one smaller number than it (1).
For nums[4]=3 there exist three smaller numbers than it (1, 2 and 2).

Example 2:

Input: nums = [6,5,4,8]
Output: [2,1,0,3]

Example 3:

Input: nums = [7,7,7,7]
Output: [0,0,0,0]

code

var smallerNumbersThanCurrent = function(nums) {
    let array = [];
   
    for(let i= 0; i < nums.length; i++){
      let count= 0;
      for(let j = 0; j<nums.length; j++) {
        if(nums[i] > nums[j]){
          count++
        }
      } 
      array.push(count);
    }
  return array;
};

1281. Subtract the Product and Sum of Digits of an Integer

Example 1:

Input: n = 234
Output: 15
Explanation:
Product of digits = 2 3 4 = 24
Sum of digits = 2 + 3 + 4 = 9
Result = 24 - 9 = 15

Example 2:

Input: n = 4421
Output: 21
Explanation:
Product of digits = 4 4 2 * 1 = 32
Sum of digits = 4 + 4 + 2 + 1 = 11
Result = 32 - 11 = 21

code

var subtractProductAndSum = function(n) {
    let arr = n.toString().split("")
    
    let multiply = arr.reduce((prev, curr) => {
      return Number(prev * curr)
    })
    
    let sum = arr.reduce((prev, curr) => {
      return Number(prev) + Number(curr)
    })
    
    return multiply - sum
};