#include<iostream>

#include<cstdio>

#include<cstring>

#include<algorithm>

#define within(x,a,b) ((unsigned)((x)-(a))<=((b)-(a)))

using namespace std;

int readint(int *p)

{

    int ch;

    while(!within(ch=getchar(),'',''))

        if(ch == EOF) return EOF;

    int rslt = ;

    do

        rslt=rslt*+(ch-'');

    while(within(ch=getchar(),'',''));

    *p = rslt;

    return ;

}

void out(int a)

{

    if(a>)

        out(a/);

    putchar(a%+'');

}

int a[];

int main()

{

    int x;

    while(cin>>x)

    {

        memset(a,,sizeof(a));

        int floor=,max=,maxfloor=,looop=,MAXS=;

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

        {

            readint(&a[i]);

            if(a[i]>maxfloor) {maxfloor=a[i];}

        }

        while(floor<=maxfloor)

        {

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

            {

                if(a[i]>=floor)

                {

                    looop++;

                }

                else if(a[i]<floor)

                {

                    if(looop>max) max=looop;

                    looop=;

                }

                if(looop>max) max=looop;

            }

            int yy=max*floor;

            if(yy>MAXS) MAXS=yy;

            floor++;

            looop=;

            max=;

        }

        out(MAXS);

        cout<<endl;

    }

    return ;

}