結果

問題 No.1181 Product Sum for All Subsets
ユーザー 👑 箱箱
提出日時 2020-11-29 01:57:41
言語 Kotlin
(1.9.23)
結果
AC  
実行時間 273 ms / 2,000 ms
コード長 2,692 bytes
コンパイル時間 15,253 ms
コンパイル使用メモリ 436,812 KB
実行使用メモリ 50,820 KB
最終ジャッジ日時 2023-10-11 02:15:47
合計ジャッジ時間 25,426 ms
ジャッジサーバーID
（参考情報） 		judge15 / judge14
このコードへのチャレンジ
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テストケース

テストケース表示
入力 結果 実行時間
実行使用メモリ
testcase_00 AC 265 ms
50,348 KB
testcase_01 AC 263 ms
50,380 KB
testcase_02 AC 265 ms
50,412 KB
testcase_03 AC 262 ms
50,500 KB
testcase_04 AC 263 ms
50,308 KB
testcase_05 AC 265 ms
50,820 KB
testcase_06 AC 264 ms
50,456 KB
testcase_07 AC 263 ms
50,292 KB
testcase_08 AC 264 ms
50,372 KB
testcase_09 AC 269 ms
50,324 KB
testcase_10 AC 269 ms
50,596 KB
testcase_11 AC 265 ms
50,288 KB
testcase_12 AC 263 ms
50,344 KB
testcase_13 AC 261 ms
50,576 KB
testcase_14 AC 268 ms
50,716 KB
testcase_15 AC 265 ms
50,496 KB
testcase_16 AC 264 ms
50,380 KB
testcase_17 AC 265 ms
50,384 KB
testcase_18 AC 266 ms
50,324 KB
testcase_19 AC 270 ms
50,328 KB
testcase_20 AC 273 ms
50,320 KB
testcase_21 AC 273 ms
50,320 KB
testcase_22 AC 270 ms
50,496 KB
testcase_23 AC 271 ms
50,300 KB
testcase_24 AC 269 ms
50,360 KB
testcase_25 AC 269 ms
50,348 KB
testcase_26 AC 270 ms
50,344 KB
testcase_27 AC 267 ms
50,344 KB
testcase_28 AC 269 ms
50,424 KB
testcase_29 AC 270 ms
50,396 KB
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ソースコード

diff # 

import java.io.InputStream
import java.io.PrintWriter
import java.util.*

// ModInt
// region
class ModInt(x: Long) {

    companion object {
        const val MOD = 1000000007L
        //const val MOD = 998244353L
    }

    val x = (x % MOD + MOD) % MOD

    operator fun plus(other: ModInt): ModInt {
        return ModInt(x + other.x)
    }

    operator fun minus(other: ModInt): ModInt {
        return ModInt(x - other.x)
    }

    operator fun times(other: ModInt): ModInt {
        return ModInt(x * other.x)
    }

    operator fun div(other: ModInt): ModInt {
        return this * other.inv()
    }

    fun pow(exp: Long): ModInt {
        if (exp == 0L) return ModInt(1L)
        var a = pow(exp shr 1)
        a *= a
        if (exp and 1L == 0L) return a
        return this * a
    }

    fun inv(): ModInt {
        return this.pow(MOD - 2)
    }

    override fun equals(other: Any?): Boolean {
        if (this === other) return true
        if (javaClass != other?.javaClass) return false

        other as ModInt

        if (x != other.x) return false

        return true
    }

    override fun hashCode(): Int {
        return x.hashCode()
    }

    override fun toString(): String {
        return "$x"
    }

}

val fac = mutableListOf<ModInt>()
val invfac = mutableListOf<ModInt>()

fun fact(n: Long, b: Boolean): ModInt {
    if (fac.count() == 0) {
        fac.add(ModInt(1))
        invfac.add(ModInt(1))
    }
    while (fac.count() <= n) {
        fac.add(fac.last() * ModInt(fac.count().toLong()))
        invfac.add(fac.last().inv())
    }
    return if (b) {
        fac[n.toInt()]
    } else {
        invfac[n.toInt()]
    }
}

fun comb(n: Long, k: Long): ModInt {
    return fact(n, true) * fact(k, false) * fact(n - k, false)
}

fun comb2(n: Long, k: Long): ModInt {
    var ans = ModInt(1)
    for (i in 0 until k) {
        ans = ans * ModInt(n - i) / ModInt(k - i)
    }
    return ans
}
// endregion

fun PrintWriter.solve() = with(FastScanner(System.`in`)) {
    val n = nextLong()
    val k = nextLong()
    val a = ModInt(k) * ModInt(k + 3) / ModInt(2)
    val b = ModInt(k) * ModInt(k + 1) / ModInt(2)
    println(a.pow(n) - b.pow(n))
}

fun main() {
    val writer = PrintWriter(System.out, false)
    writer.solve()
    writer.flush()
}

class FastScanner(s: InputStream) {
    private var st = StringTokenizer("")
    private val br = s.bufferedReader()

    fun next(): String {
        while (!st.hasMoreTokens()) st = StringTokenizer(br.readLine())
        return st.nextToken()
    }

    fun nextInt() = next().toInt()
    fun nextLong() = next().toLong()
    fun nextLine() = br.readLine()
    fun nextDouble() = next().toDouble()
}
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