392B

Solution

#include <cstdio>
#include <algorithm>
using namespace std;

const int MAX_N = 50;

int cost[3][3];
long long f[MAX_N][3][3];
int n;

int main()
{
    //input
    for (int i = 0; i < 3; i++)
        for (int j = 0; j < 3; j++)
            scanf("%d", &cost[i][j]);
    scanf("%d", &n);
    //work
    for (int i = 1; i <= n; i++)
    {
        for (int j = 0; j < 3; j++)
        {
            for (int k = 0; k < 3; k++)
            {
                if (j == k)
                    continue;
                int x = 3 - j - k;
                f[i][j][k] = f[i - 1][j][x] + cost[j][k] + f[i - 1][x][k];
                f[i][j][k] = min(f[i][j][k], f[i - 1][j][k] + cost[j][x] + f[i - 1][k][j] + cost[x][k] + f[i - 1][j][k]);
            }
        }
    }
    printf("%I64d\n", f[n][0][2]);
    return 0;
}