[백준] RGB 거리

 

https://www.acmicpc.net/problem/1149

 

fun main() = with(Scanner(System.`in`)) {
    val size = nextInt()
    val count = Array<Int>(size * 3) { 0 }
    for (i in count.indices) {
        count[i] = nextInt()
    }

    val dp = Array<Int>(count.size) { Int.MAX_VALUE }
    for (i in 0..2) {
        dp[i] = count[i]
    }

    for (i in 0 until size - 1) {
        for (j in 0..2) {
            if (j == 0) {
                dp[(i + 1) * 3 + 1] =
                    min(dp[(i + 1) * 3 + 1], dp[(i) * 3] + count[(i + 1) * 3 + 1])
                dp[(i + 1) * 3 + 2] =
                    min(dp[(i + 1) * 3 + 2], dp[(i) * 3] + count[(i + 1) * 3 + 2])
            }
            if (j == 1) {
                dp[(i + 1) * 3 + 0] =
                    min(dp[(i + 1) * 3 + 0], dp[(i) * 3 + 1] + count[(i + 1) * 3 + 0])
                dp[(i + 1) * 3 + 2] =
                    min(dp[(i + 1) * 3 + 2], dp[(i) * 3 + 1] + count[(i + 1) * 3 + 2])
            }
            if (j == 2) {
                dp[(i + 1) * 3 + 0] = min(dp[(i + 1) * 3 + 0], dp[(i) * 3 + 2]  + count[(i + 1) * 3 + 0])
                dp[(i + 1) * 3 + 1] = min(dp[(i + 1) * 3 + 1], dp[(i) * 3 + 2]  + count[(i + 1) * 3 + 1])
            }
        }
    }
    println(dp.takeLast(3).min())
}