#include<bits/stdc++.h>
using namespace std;
long Compute(long x);
long n,x[20],minor,rankn;
int main(void)
{
    scanf("%d",&n);
    for(int i=0;i<n;i++) scanf("%1d",&x[i]);
    for(int i=0;i<n;i++)
    {
        minor=0;
        for(int j=i+1;j<n;j++)
        {
            if(x[j]<x[i]) minor++;
        }
        rankn+=minor*Compute(n-1-i);
    }
    cout<<rankn+1;
    return 0;
}
long Compute(long x)
{
    if(x==1) return 1;
    else if(x>1) return x*Compute(x-1);
    else return -1;
}