C++ :

#include<cstdio>
using namespace std;
int n,i,a=0,b,ans=0;
int main()
{
	scanf("%d",&n);
	for(i=1;i<=n;i++)
	{
		scanf("%d",&b);
		if(a<b)ans+=(b-a);
		a=b;
	}
	printf("%d",ans);
	return 0;
}

Pascal :

var
   n,x,ans,i,y:longint;
begin
 readln(n);
 read(x);
 ans:=x;
 for i:=2 to n do
  begin
   read(y);
   if x<y then ans:=ans+(y-x);
   x:=y;
  end;
 writeln(ans);
end.

Java :

import java.util.Scanner;

public class Main {
    public static void main(String[] args){
        Scanner scanner = new Scanner(System.in);
        int n = scanner.nextInt();
        int d[] = new int[100005];
        for(int i=0;i<n;i++){
            d[i] = scanner.nextInt();
        }
        int ans = 0;
        for(int i=1;i<n;i++){
            if (d[i]>d[i-1])
                ans+=d[i]-d[i-1];
        }
        System.out.println(ans+d[0]);
    }
}
/*
#include <bits/stdc++.h>
#include <iostream>
using namespace std;
int n,ans=0;
int d[100005];
int main ()
{
    cin >> n;
    for (int i=0;i<n;i++)
        cin >> d[i];
    for (int i=1;i<n;i++)
        if (d[i]>d[i-1])
            ans+=d[i]-d[i-1];
    cout << ans+d[0];
}
 */