[LeetCode/Swift] 1672. Richest Customer Wealth

💡 문제 (Easy)

Richest Customer Wealth - LeetCode

You are given an m x n integer grid accounts where accounts[i][j] is the amount of money the i​​​​​​​​​​​th​​​​ customer has in the j​​​​​​​​​​​th​​​​ bank. Return the wealth that the richest customer has.
A customer's wealth is the amount of money they have in all their bank accounts. The richest customer is the customer that has the maximum wealth.

 

Example 1:
Input: accounts = [[1,2,3],[3,2,1]]
Output: 6
Explanation:
1st customer has wealth = 1 + 2 + 3 = 6
2nd customer has wealth = 3 + 2 + 1 = 6
Both customers are considered the richest with a wealth of 6 each, so return 6.

Example 2:
Input: accounts = [[1,5],[7,3],[3,5]]
Output: 10
Explanation: 
1st customer has wealth = 6
2nd customer has wealth = 10 
3rd customer has wealth = 8
The 2nd customer is the richest with a wealth of 10.

Example 3:
Input: accounts = [[2,8,7],[7,1,3],[1,9,5]]
Output: 17

Constraints:
m == accounts.length
n == accounts[i].length
1 <= m, n <= 50
1 <= accounts[i][j] <= 100

 

👩🏻‍💻 해결

1차 : for문 사용

class Solution {
    func maximumWealth(_ accounts: [[Int]]) -> Int {
        var sumAccounts: [Int] = []
        
        for account in accounts {
            var sum: Int = 0
            for acc in account {
                sum += acc
            }
            sumAccounts.append(sum)
        }

        return sumAccounts.max() ?? 0
    }
}

 

2차 : reduce 사용

class Solution {
    func maximumWealth(_ accounts: [[Int]]) -> Int {
        return accounts.reduce(0, { max($0, $1.reduce(0, +)) })
    }
}