Problem:
Score : 300 points

Problem Statement

In a flower bed, there are N flowers, numbered 1,2,......,N. Initially, the heights of all flowers are 0.
You are given a sequence h=\{h_1,h_2,h_3,......\} as input. You would like to change the height of Flower k to h_k for all k (1 \leq k \leq N), by repeating the following "watering" operation:

Specify integers l and r. Increase the height of Flower x by 1 for all x such that l \leq x \leq r.

Find the minimum number of watering operations required to satisfy the condition.

Constraints

1 \leq N \leq 100

0 \leq h_i \leq 100

All values in input are integers.

Input

Input is given from Standard Input in the following format:

N
h_1 h_2 h_3 ...... h_N

Output

Print the minimum number of watering operations required to satisfy the condition.

Sample Input 1

4
1 2 2 1

Sample Output 1

2

The minimum number of watering operations required is 2.
One way to achieve it is:

Perform the operation with (l,r)=(1,3).

Perform the operation with (l,r)=(2,4).

Sample Input 2

5
3 1 2 3 1

Sample Output 2

5

Sample Input 3

8
4 23 75 0 23 96 50 100

Sample Output 3

221

Solution in C++14 (GCC 5.4.1) (judge verdict: Wrong Answer)

#include<iostream>
using namespace std;
int main() {
    int n; cin >> n;
    int h[100] = {0};
    int Min = 100;
    for (int i = 0; i < n; ++i) {
        cin >> h[i];
        if (Min > h[i]) {
            Min = h[i];
        }
    }
    for (int i = 0; i < n; ++i) {
        h[i] -= Min;
    }
    int Delete = 0;
    int Sum = Min;
    for (int i = 0; i < n; ++i) {
        if (Delete < h[i]) {
            Delete = h[i];
        }
        if (h[i] != 0 && h[i + 1] == 0) {
            Sum += Delete;
            Delete = 0;
        }
    }
    cout << Sum << endl;
    return 0;
}