백준 - ATM (11399)

let N = Int(readLine()!)!
let P = readLine()!.split(separator: " ").map{ Int(String($0))! }.sorted()
var sumArr = [P[0]]

for i in 1..<N {
    sumArr.append(sumArr[i-1] + P[i])
}

print(sumArr.reduce(0, +))