//Ненавижу 1С для mista.ru
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;
namespace ConsoleApp7
{
class Program
{
static void Main(string[] args)
{
var result = 0;
var s = Console.ReadLine();
var builds = s.Split(' ').Select(c => Int32.Parse(c)).ToList();
int last = builds.Count()-1;
int based = 0;
while(based!=last)
{
var nextBased = based;
var maxIndex = based+1;
for (int i=based+1;i<=last;i++)
{
if(builds[i]>builds[based])
{
nextBased = i;
break;
}
else if(builds[i]>=builds[maxIndex])
{
maxIndex = i;
}
}
if(nextBased==based)
{
nextBased = maxIndex;
}
var level = Math.Min(builds[based], builds[nextBased]);
for(int i=based+1;i<nextBased;i++)
{
result += (level - builds[i]);
}
based = nextBased;
}
Console.WriteLine(result);
Console.ReadKey();
}
}
}
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