#include <cstdio>
#include <cmath>
#include <vector>
#include <algorithm>
using namespace std;

int main() {
	int K = 0, N = 0, S = 1;
	scanf("%d %d %d", &N, &K, &S);
	vector<int> p;
	int temp = 0;
	for (int i = 0; i < N; i++) {
		scanf("%d", &temp);
		p.push_back(temp);
	}

	for (int i = 0; i < p.size(); i++) {
		p[i] = p[i] / S + (p[i] % S > 0);
		if (i > 0) {
			p[i] += p[i-1];
		}
	}

	int t = 2000000000;
	for (int i = 0, k = K; i < p.size(); i++) {
		k = K;
		for (int j = 0, mod = 0; j < p.size(); j++) {
			if (k < 0) {
				break;
			}
			if (p[j] - mod >= p[i]) {
				k--;
				mod = p[j];
			}
		}
		if (k >= 0) {
			t = min(t, p[i]);
		}
	}

	printf("%d", t);
}