[Swift] 땅따먹기

import Foundation

func solution(_ land:[[Int]]) -> Int{
    var land = land
    
    for i in 0..<land.count-1 {
        land[i+1][0] += max(land[i][1], land[i][2], land[i][3])
        land[i+1][1] += max(land[i][0], land[i][2], land[i][3])
        land[i+1][2] += max(land[i][0], land[i][1], land[i][3])
        land[i+1][3] += max(land[i][0], land[i][1], land[i][2])
    }
   
    return land.last!.max()!
}