import std.algorithm, std.array, std.container, std.range;
import std.string, std.conv, std.math, std.random;
import std.stdio, std.typecons;

void main()
{
  auto rd = readln.split.map!(to!int);
  auto n = rd[0];
  auto k = rd[1];
  auto si = readln.chomp.map!(to!string).map!(to!int).array;

  auto ti = new int[n];
  ti[0] = 1;
  auto a = si[0];
  foreach (i; 1..n) {
    if (a > 0) {
      ti[i] = ti[i - 1];
      a -= 1;
    } else {
      ti[i] = ti[i - 1] + 1;
    }

    a += si[i];
  }

  int r;
  if (k <= n) {
    r = ti[k - 1];
  } else {
    r = ti.back;
    if (ti.back >= a) {
      r += (k / n - 1) * (ti.back - a);
      if (k % n != 0)
	r += max(ti[k % n - 1] - a, 0);
    }
  }

  writeln(r);
}