import java.util.Scanner;

public class Main {
    public static void main(String[] args) {
        Scanner sc = new Scanner(System.in);
        int n = sc.nextInt();
        int V = sc.nextInt();
        int[] a = new int[n];
        input(sc, a);
        int count = 1;
        int v = V;
        for (int i = 0; i < a.length; ) {
            if (v >= a[i]) {
                v -= a[i++];
            } else {
                v = V;
                count++;
            }
        }
        System.out.println(count);
    }

    static void input(Scanner sc, int[] a) {
        for (int i = 0; i < a.length; i++) {
            a[i] = sc.nextInt();
        }
    }
}