#include <cstdio>

#include <cmath>

#include <set>

#include <cstring>

#include <algorithm>

using namespace std;

int p;

int a[1000010],sz;

char s[1000010];

void work()

{

    int sum=0;

    for(int i=0;s[i];i++)

    {

        sum++;

        if(s[i]==' ')

        {

            a[sz++] = sum;

            sum=0;

        }

        else if(s[i]=='-')

        {

            a[sz++] = sum;

            sum=0;

        }

    }

    if(sum)

    {

        a[sz++] = sum;

    }

}

bool check(int x)

{

    int sum=0;

    int y=0;

    for(int i=0;i<sz;i++)

    {

        if(a[i]>x) return 0;

    }

    for(int i=0;i<sz;i++)

    {

        if(sum+a[i]<=x)

        {

            sum=sum+a[i];

        }

        else

        {

            sum = a[i];

            y++;

        }

    }

    if(sum) y++;

    if(y<=p) return 1;

    return 0;

}

int main()

{

    scanf("%d",&p);

    getchar();

    gets(s);

    work();

    int ans,L=1,R=1000000;

    while(L<=R)

    {

        int mid = (L+R)/2;

        if(check(mid)) ans = mid,R = mid-1;

        else L = mid+1;

    }

    printf("%d\n",ans);

    return 0;

}