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 Go (1.6) (judge verdict: Accepted)

package main

import "fmt"
import "os"
import "io/ioutil"
import "unsafe"
import "strings"
import "math"

func main() {
	input, _ := ioutil.ReadAll(os.Stdin)
	r := strings.NewReader(bstring(input))

	var N, A, B float64
	fmt.Fscanf(r, "%v %v %v", &N, &A, &B)

	plan1 := N * A
	plan2 := B

	fmt.Println(math.Min(plan1, plan2))
}

func bstring(b []byte) string {
	return *(*string)(unsafe.Pointer(&b))
}