Problem:
Score : 100 points

Problem Statement

You are parking at a parking lot. You can choose from the following two fee plans:

Plan 1: The fee will be A×T yen (the currency of Japan) when you park for T hours.

Plan 2: The fee will be B yen, regardless of the duration.

Find the minimum fee when you park for N hours.

Constraints

1≤N≤20

1≤A≤100

1≤B≤2000

All input values are integers.

Input

Input is given from Standard Input in the following format:

N A B

Output

When the minimum fee is x yen, print the value of x.

Sample Input 1

7 17 120

Sample Output 1

119

If you choose Plan 1, the fee will be 7×17=119 yen.

If you choose Plan 2, the fee will be 120 yen.

Thus, the minimum fee is 119 yen.

Sample Input 2

5 20 100

Sample Output 2

100

The fee might be the same in the two plans.

Sample Input 3

6 18 100

Sample Output 3

100

Solution in C# (Mono 4.6.2.0) (judge verdict: Accepted)

using System;
using System.Collections.Generic;
using System.Linq;
#if !DEBUG
    using System.IO;
#endif

public class Program {
    public static void Main() {
        #region SetAutoFlushIsFalse
#if !DEBUG
        var sw = new StreamWriter(Console.OpenStandardOutput()) { AutoFlush = false };
        Console.SetOut(sw);
#endif
        #endregion
        var arr = ReadLib.ReadAsIntArray();
        var score = Math.Min(arr[2], arr[0] * arr[1]);
        Console.WriteLine(score);
        #region Flush
#if !DEBUG
        Console.Out.Flush();
        sw.Close();
#endif
        #endregion
    }

    private static string Compare(string a, string b) {
        if (a.Length != b.Length) {
            return a.Length > b.Length ? "GREATER" : "LESS";
        }

        var size = a.Length;
        for (int i = 0; i < size; i++) {
            var an = int.Parse(a[i].ToString());
            var bn = int.Parse(b[i].ToString());
            if (an != bn) {
                return an > bn ? "GREATER" : "LESS";
            }
        }
        return "EQUAL";
    }
}

static class ReadLib {
    public static long ReadAsLong() {
        return long.Parse(Console.ReadLine());
    }

    public static int ReadAsInt() {
        return int.Parse(Console.ReadLine());
    }

    public static int[] ReadAsIntArray() {
        return Console.ReadLine().Split(' ').Select(s => int.Parse(s)).ToArray();
    }

    public static long[] ReadAsLongArray() {
        return Console.ReadLine().Split(' ').Select(s => long.Parse(s)).ToArray();
    }

    public static ulong[] ReadAsULongArray() {
        return Console.ReadLine().Split(' ').Select(s => ulong.Parse(s)).ToArray();
    }

    public static string[] ReadAsStringArray() {
        return Console.ReadLine().Split(' ');
    }

    public static int[] ReadNTimesAsInt(int n) {
        return Enumerable.Range(1, n).Select(s => int.Parse(Console.ReadLine())).ToArray();
    }

    public static int[][] ReadNTimesAsIntArray(int n) {
        return Enumerable.Range(1, n).Select(s => ReadAsIntArray()).ToArray();
    }

}

static class MyMath {
    /// <summary>階乗</summary>
    public static long Factorial(int n) {
        if (n == 0) {
            return 1;
        }

        return Permutation(n, 0);
    }

    public static long Permutation(int n, int k) {
        return Enumerable.Range(0, n - k).Select(i => n - i).Aggregate(1, (b, i) => b * i);
    }

    /// <summary>nCr, 組み合わせ</summary>
    public static long Combination(int n, int r) {
        if (r == 0) {
            return 1;
        }
        // 分子
        var moleculeArr = Enumerable
            .Range(0, Math.Min(n - r, r))
            .Select(i => n - i)
            .ToArray();
        var moleculeArrLength = moleculeArr.Length;
        // 分母
        var denominatorArr = Enumerable
            .Range(1, Math.Max(n - r, r))
            .ToArray();

        for (var m = 0; m < moleculeArrLength; m++) {
            while (true) {
                var mVal = moleculeArr[m];
                var gcds = denominatorArr.Select(b => Gcd(mVal, b));
                var maxGcd = gcds.Max();
                var maxI = gcds.ToList().IndexOf(maxGcd);

                if (maxGcd == 1) {
                    break;
                }

                denominatorArr[maxI] /= maxGcd;
                moleculeArr[m] /= maxGcd;
            }
        }

        return FullPower(moleculeArr);
    }

    #region FullPower
    /// <summary>総乗、π</summary>
    public static long FullPower(IEnumerable<long> vs) {
        return vs.Aggregate(1L, (a, b) => a * b);
    }

    public static long FullPower(IEnumerable<int> vs) {
        return vs.Aggregate(1L, (a, b) => a * b);
    }
    #endregion

    /// <summary>最大公約数</summary>
    public static int Gcd(long item1, long item2) {
        var a = Math.Max(item1, item2);
        var b = Math.Min(item1, item2);

        while (true) {
            var mod = a % b;
            if (mod == 0) {
                break;
            }

            a = b;
            b = mod;
        }
        return (int)b;
    }

    /// <summary>約分。最大公約数で割ったものを返す。</summary>
    public static Tuple<long, long> DeviedByGcd(long item1, long item2) {
        var gcd = Gcd(item1, item2);
        return new Tuple<long, long>(item1 / gcd, item2 / gcd);
    }
}

//static class IEnumerableExtention {
//    public static int IndexOfMax<T>(this IEnumerable<T> ts) {
//        var max = ts.Max();
//        return ts.ToList().IndexOf(max);
//    }

//    public static int IndexOfMax<T>(this IEnumerable<T> ts, Func<T, int> func) {
//        var funced = ts.Select(i => func(i));
//        var max = ts.Max(func);
//        return funced.ToList().IndexOf(max);
//    }

//    public static int IndexOfMax<T>(this IEnumerable<T> ts, Func<T, long> func) {
//        var funced = ts.Select(i => func(i));
//        var max = ts.Max(func);
//        return funced.ToList().IndexOf(max);
//    }
//}