#include <stdio.h>

int main(int argc, char *argv[], char env[])
{
        int first, second;
        int answer;

        if(argc != 3)
        {
                printf("bad input\n");
                return 1;
        }

        first = atoi(argv[1]);
        second = atoi(argv[2]);

        answer = (50 * first) + ((50 * first) / (0.8 + (0.2 * second)));

        printf("%d\n",answer);

        return 0;
}