Painting Fence 448C Codeforces

//QUESTION - https://codeforces.com/problemset/problem/448/C
// TODO - MEMO/DP..recursive solution written
#include <bits/stdc++.h>
using namespace std;

void getMinimumStrokes(int level, long long strokes, long long &minStrokes, vector<int> &fence){
    if(level >= fence.size()){
     minStrokes = min(minStrokes, strokes);
     return;
    }

    // If section is already painted, move to the next section
    if(fence[level] == 0){
        getMinimumStrokes(level + 1, strokes, minStrokes, fence);
    }

    // Else we have 2 ways of painting (H, V);
    else{
        //horizontal stroke
        int paintedTill = -1;
        for(int i = level; i < fence.size(); i++){
            if(fence[i] == 0){
                break;
            }
            paintedTill = i;
            fence[i]--;
        }
        getMinimumStrokes(level, strokes + 1, minStrokes, fence);
        // backtrack to previous state where horizontal stroke didn't happen
        int actualRangePainted = paintedTill == -1 ? fence.size() - 1: paintedTill;
            if(paintedTill != -1){
                for(int i = level; i <= paintedTill; i++){
                fence[i]++;
            }
        }

        //vertical stroke
        int currUnpaintedFence = fence[level];
        fence[level] = 0;
        getMinimumStrokes(level + 1, strokes + 1, minStrokes, fence);
        fence[level] = currUnpaintedFence;
    }
}

int main() {
    // your code goes here
    int n;
    cin >> n;
    vector<int> fence(n);
    for(int i = 0; i < n; i++){
        cin >> fence[i];
    }
    long long minStrokes = INT_MAX;
    getMinimumStrokes(0, 0, minStrokes, fence);
    cout << minStrokes << '\n';
}