29 Nov 2020 | Boredom-and-Leetcoding
Difficulty
Easy

Hey viewer! Hope you’re having a fantastic day. Today I decided to do some leetcoding again.

This was pretty easy, to be honest, but I’m just not feeling up to anything super challenging at the moment.

Very straightforward solution with a mild optimization to avoid going through n^2 pairs.

class Solution {
public int numIdenticalPairs ( int [] nums ) {
int goodPairs = 0 ;
for ( int i = 0 ; i < nums . length ; i ++) {
for ( int j = i + 1 ; j < nums . length ; j ++) {
if ( i != j && i < j && nums [ i ] == nums [ j ]) {
goodPairs ++;
}
}
}
return goodPairs ;
}
}

Difficulty
Easy

Again, incredibly easy…

class Solution {
public int maximumWealth ( int [][] accounts ) {
int highestAccount = 0 ;
for ( int i = 0 ; i < accounts . length ; i ++) {
int accountTotal = 0 ;
for ( int j = 0 ; j < accounts [ i ]. length ; j ++) {
accountTotal += accounts [ i ][ j ];
}
if ( accountTotal > highestAccount ) {
highestAccount = accountTotal ;
}
}
return highestAccount ;
}
}

Difficulty
Easy

I know, I know…this is literally elementary, but I haven’t solved this yet! I’m just going through problems I haven’t done before okay!

class Solution {
public int [] runningSum ( int [] nums ) {
int [] runningSum = new int [ nums . length ];
int sum = 0 ;
for ( int i = 0 ; i < nums . length ; i ++) {
sum += nums [ i ];
runningSum [ i ] = sum ;
}
return runningSum ;
}
}

Difficulty
Easy

So, this one is actually a bit trickier. I’m sure there’s an optimization to be made here, but I went with an obvious solution and it was actually fast enough to pass. Let me know if you know of a better way to do this. I was thinking about incrementally stepping through both arrays at the same time, but they may not have the same lengths so it could get weird…that’s why I opted for a concise solution.

class Solution {
public boolean arrayStringsAreEqual ( String [] word1 , String [] word2 ) {
StringBuilder sb = new StringBuilder ();
for ( String x : word1 ) {
sb . append ( x );
}
StringBuilder sb2 = new StringBuilder ();
for ( String y : word2 ) {
sb2 . append ( y );
}
return sb . toString (). equalsIgnoreCase ( sb2 . toString ());
}
}

This one is pretty straightforward, although it’s easy to do this in a really stupid way.

My submission is apparently faster than 99.73% of online submissions.

Difficulty
Easy

class ParkingSystem {
int [] spots = new int [ 3 ];
public ParkingSystem ( int big , int medium , int small ) {
spots [ 0 ] = big ;
spots [ 1 ] = medium ;
spots [ 2 ] = small ;
}
public boolean addCar ( int carType ) {
if ( carType == 1 ) {
return updateSpots ( 0 );
} else if ( carType == 2 ) {
return updateSpots ( 1 );
} else {
return updateSpots ( 2 );
}
}
public boolean updateSpots ( int spotId ) {
if ( spots [ spotId ] > 0 ) {
spots [ spotId ]--;
return true ;
}
return false ;
}
}
/**
* Your ParkingSystem object will be instantiated and called as such:
* ParkingSystem obj = new ParkingSystem(big, medium, small);
* boolean param_1 = obj.addCar(carType);
*/