7-2

#include <stdio.h>

int main() {
    double a[6][4], mult = 1;
    scanf("%lf", &a[0][0]);
    double min = a[0][0];

    for (int i = 0; i < 6; ++i) {
        for (int j = 0; j < 4; ++j) {
            if (!(i == 0 && j == 0)) {
                scanf("%lf", &a[i][j]);
                min = a[i][j] < min ? a[i][j] : min;
            }
        }
    }

    for (int i = 0; i < 6; ++i) {
        for (int j = 0; j < 4; ++j) {
            if (a[i][j] == min) {
                mult *= a[i][j];
            }
        }
    }

    printf("%lf", mult);

    return 0;
}