Bond100

#include<stdio.h>

int n;

double value[20][20];

double max(double a,double b){
    return (a > b ? a : b);
}

/*
double cal(int order,int check){
    if(check == (1<<n)-1){
        return 1;
    }
    double ans = 0;
    for(int i = 0 ; i < n ; i ++){
        if((check & (1<<i)) == 0){ //and use
            ans = max(ans,cal(order+1,(check | (1<<i)))*(value[i][order]/100)    );
        }
    }
    return ans;
}
*/
int main()
{
    scanf("%d",&n);
    for(int i = 0 ; i < n ; i ++){
        for(int j = 0 ; j < n ; j ++){
            scanf("%lf",&value[i][j]);
        }
    }
    double dp[1<<n];

    for(int check = (1<<n)-1 ; check >= 0 ; check --){
        int order = __builtin_popcount(check);
        if(check == (1<<n)-1 || order == n){
            dp[check] = 1;
            continue;
        }
        double ans = 0;
        for(int i = 0 ; i < n ; i ++){
            if((check & (1<<i)) == 0){ //and use
                double d;
                if(order+1 == n){
                    d = 1;
                }
                else{
                    d = dp[(check | (1<<i))];
                }
                ans = max(ans,d * (value[i][order]/100));
            }
        }
        dp[check] = ans;
    }
    printf("%lf",dp[0]*100);
    return 0;
}