import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        }
    }
}


class Takoyaki {

	int getCountOfBake(int numOfCanBeBakedAtOneTime, int numOfWant) {
		if (numOfWant % numOfCanBeBakedAtOneTime > 0) {
			return (numOfWant / numOfCanBeBakedAtOneTime) + 1;
		}
		return numOfWant / numOfCanBeBakedAtOneTime;
	}

	public int getTimeOfBake(int n, int x, int bakeTimeUnit) {
		int bakeCount = this.getCountOfBake(x, n);
		return bakeTimeUnit * bakeCount;
	}
} import java.util.Scanner; Scanner java.util public class Main {
    public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        }
    }
} Main public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        }
    } main {
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        }
    } try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        } {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        } Scanner scanner = new Scanner(System.in) Scanner scanner = new Scanner(System.in) new Scanner(System.in) int n = scanner.nextInt(); n scanner.nextInt() scanner.nextInt scanner int x = scanner.nextInt(); x scanner.nextInt() scanner.nextInt scanner int t = scanner.nextInt(); t scanner.nextInt() scanner.nextInt scanner Takoyaki takoyaki = new Takoyaki(); takoyaki new Takoyaki() System.out.println(takoyaki.getTimeOfBake(n, x, t)) System.out.println System.out System System.out takoyaki.getTimeOfBake(n, x, t) takoyaki.getTimeOfBake takoyaki n x t String[] args args class Takoyaki {

	int getCountOfBake(int numOfCanBeBakedAtOneTime, int numOfWant) {
		if (numOfWant % numOfCanBeBakedAtOneTime > 0) {
			return (numOfWant / numOfCanBeBakedAtOneTime) + 1;
		}
		return numOfWant / numOfCanBeBakedAtOneTime;
	}

	public int getTimeOfBake(int n, int x, int bakeTimeUnit) {
		int bakeCount = this.getCountOfBake(x, n);
		return bakeTimeUnit * bakeCount;
	}
} Takoyaki int getCountOfBake(int numOfCanBeBakedAtOneTime, int numOfWant) {
		if (numOfWant % numOfCanBeBakedAtOneTime > 0) {
			return (numOfWant / numOfCanBeBakedAtOneTime) + 1;
		}
		return numOfWant / numOfCanBeBakedAtOneTime;
	} getCountOfBake {
		if (numOfWant % numOfCanBeBakedAtOneTime > 0) {
			return (numOfWant / numOfCanBeBakedAtOneTime) + 1;
		}
		return numOfWant / numOfCanBeBakedAtOneTime;
	} if (numOfWant % numOfCanBeBakedAtOneTime > 0) {
			return (numOfWant / numOfCanBeBakedAtOneTime) + 1;
		} numOfWant % numOfCanBeBakedAtOneTime > 0 numOfWant % numOfCanBeBakedAtOneTime numOfWant numOfCanBeBakedAtOneTime 0 {
			return (numOfWant / numOfCanBeBakedAtOneTime) + 1;
		} return (numOfWant / numOfCanBeBakedAtOneTime) + 1; (numOfWant / numOfCanBeBakedAtOneTime) + 1 (numOfWant / numOfCanBeBakedAtOneTime) numOfWant numOfCanBeBakedAtOneTime 1 return numOfWant / numOfCanBeBakedAtOneTime; numOfWant / numOfCanBeBakedAtOneTime numOfWant numOfCanBeBakedAtOneTime int numOfCanBeBakedAtOneTime numOfCanBeBakedAtOneTime int numOfWant numOfWant public int getTimeOfBake(int n, int x, int bakeTimeUnit) {
		int bakeCount = this.getCountOfBake(x, n);
		return bakeTimeUnit * bakeCount;
	} getTimeOfBake {
		int bakeCount = this.getCountOfBake(x, n);
		return bakeTimeUnit * bakeCount;
	} int bakeCount = this.getCountOfBake(x, n); bakeCount this.getCountOfBake(x, n) this.getCountOfBake this x n return bakeTimeUnit * bakeCount; bakeTimeUnit * bakeCount bakeTimeUnit bakeCount int n n int x x int bakeTimeUnit bakeTimeUnit public class Main {
    public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        }
    }
} public class Main {
    public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        }
    }
} Main
import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        try (Scanner scanner = new Scanner(System.in)) {
            int n = scanner.nextInt();
            int x = scanner.nextInt();
            int t = scanner.nextInt();

            Takoyaki takoyaki = new Takoyaki();
            System.out.println(takoyaki.getTimeOfBake(n, x, t));
        }
    }
}


class Takoyaki {

	int getCountOfBake(int numOfCanBeBakedAtOneTime, int numOfWant) {
		if (numOfWant % numOfCanBeBakedAtOneTime > 0) {
			return (numOfWant / numOfCanBeBakedAtOneTime) + 1;
		}
		return numOfWant / numOfCanBeBakedAtOneTime;
	}

	public int getTimeOfBake(int n, int x, int bakeTimeUnit) {
		int bakeCount = this.getCountOfBake(x, n);
		return bakeTimeUnit * bakeCount;
	}
}