#include<stdio.h>

#include<string.h>

int m,t,n;

double dp[][][],p[][],tt[][];

int main()

{

    int i,j,k;

    while(~scanf("%d%d%d",&m,&t,&n))

    {

        if (!m && !t && !n)

            break;

        memset(dp,0.0,sizeof(dp));

        memset(tt,0.0,sizeof(tt));

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

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

            {

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

            }

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

        {

            dp[i][][] = 1.0;

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

            {

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

            }

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

            {

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

                {

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

                }

            }

            tt[i][] = dp[i][m][];

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

            {

                tt[i][k] = tt[i][k-] + dp[i][m][k];

            }

        }

        double p1 = 1.0,p2=1.0;

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

        {

            p1 *= (tt[i][m]-tt[i][]);

            p2 *= (tt[i][n-]-tt[i][]);

        }

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

    }

    return  ;

}