#include<cstdio>

#define N 1001

#define T 31

double dp[N][T][T];

double p[N][T];

int main()

{

    int m, t, n;

    while (scanf("%d%d%d", &m, &t, &n) != EOF, m || n || t)

    {

        for (int i = ; i <= t;++i)

        for (int j = ; j <= m; ++j)

            scanf("%lf", &p[i][j]);

        for (int i = ; i <= t; ++i)

        {

            dp[i][][] = ;

            for (int j = ; j <= m;++j)

            for (int k = ; k <= j; ++k)

            {

                dp[i][j][k] = dp[i][j-][k] * ( - p[i][j]);

                if (k != )dp[i][j][k]+=dp[i][j-][k - ] * p[i][j];

            }

        }

        double p1 = ;

        //利用母函数

        for (int i = ; i <= t; ++i)

        {

            double ans = ;

            for (int k = ; k <= m; ++k)

                ans += dp[i][m][k];

            p1 *= ans;

        }

        double p2 = ;

        for (int i = ; i <= t; ++i)

        {

            double ans = ;

            for (int k = ; k < n; ++k)

                ans += dp[i][m][k];

            p2 *= ans;

        }

        printf("%.3lf\n", p1 - p2);

    }

}