import java.util.Scanner;
public class Main{
public static void main(String[] args){
Scanner sc = new Scanner(System.in);
int N = sc.nextInt();
int n = sc.nextInt();
int[] d = new int[n+1];
int y = 0;
int l = 0;
for(int i=0;i<n+1;i++){
d[i] = sc.nextInt();
if(d[i]>N){
System.out.println(0);
return;
}
}
for(int i=0;i<n;i++){
if(l==0){
l = d[i]+d[i+1];
}else{
l = l+d[i+1];
}
if(l>N){
y++;
l=0;
}
}
System.out.println(y);
}
}
public class Main {
public static void main(String[] args) {
Scanner sc = new Scanner(System.in);
int N = sc.nextInt();
int n = sc.nextInt();
int[] d = new int[n + 1];
int y = 0;
int l = 0;
for (int i = 0; i < n + 1; i++) {
d[i] = sc.nextInt();
if (d[i] > N) {
System.out.println(0);
return;
}
}
for (int i = 0; i < n; i++) {
l = l - d[i];
if (l < d[i + 1]) {
y++;
l = N;
}
}
System.out.println(y);
}
}