#include <bits/stdc++.h>

struct dsu {
  dsu() {}
  explicit dsu(int n) : _cc(n), dat(n, -1) {}

  int size() const { return std::size(dat); }
  int root(int v) {
    assert(0 <= v), assert(v < size());
    return dat[v] < 0 ? v : dat[v] = root(dat[v]);
  }
  std::pair<int, int> unite(int u, int v) {
    assert(0 <= u), assert(u < size());
    assert(0 <= v), assert(v < size());
    u = root(u), v = root(v);
    if (u == v) return {u, -1};
    --_cc;
    if (-dat[u] < -dat[v]) std::swap(u, v);
    dat[u] += dat[v];
    dat[v] = u;
    return {u, v};
  }
  bool same(int u, int v) {
    assert(0 <= u), assert(u < size());
    assert(0 <= v), assert(v < size());
    return root(u) == root(v);
  }
  int size(int v) {
    assert(0 <= v), assert(v < size());
    return -dat[root(v)];
  }
  int cc() const { return _cc; }

 private:
  int _cc;
  std::vector<int> dat;
};

#pragma region my_template

struct Rep {
  struct I {
    int i;
    void operator++() { ++i; }
    int operator*() const { return i; }
    bool operator!=(I o) const { return i < *o; }
  };
  const int l, r;
  Rep(int _l, int _r) : l(_l), r(_r) {}
  Rep(int n) : Rep(0, n) {}
  I begin() const { return {l}; }
  I end() const { return {r}; }
};
struct Per {
  struct I {
    int i;
    void operator++() { --i; }
    int operator*() const { return i; }
    bool operator!=(I o) const { return i > *o; }
  };
  const int l, r;
  Per(int _l, int _r) : l(_l), r(_r) {}
  Per(int n) : Per(0, n) {}
  I begin() const { return {r - 1}; }
  I end() const { return {l - 1}; }
};

template <class F>
struct Fix : private F {
  Fix(F f) : F(f) {}
  template <class... Args>
  decltype(auto) operator()(Args&&... args) const {
    return F::operator()(*this, std::forward<Args>(args)...);
  }
};

template <class T = int>
T scan() {
  T res;
  std::cin >> res;
  return res;
}

template <class T, class U = T>
bool chmin(T& a, U&& b) {
  return b < a ? a = std::forward<U>(b), true : false;
}
template <class T, class U = T>
bool chmax(T& a, U&& b) {
  return a < b ? a = std::forward<U>(b), true : false;
}

#ifndef LOCAL
#define DUMP(...) void(0)
template <int OnlineJudge, int Local>
constexpr int OjLocal = OnlineJudge;
#endif

using namespace std;

#define ALL(c) begin(c), end(c)

#pragma endregion

int main() {
  cin.tie(nullptr)->sync_with_stdio(false);
  cout << fixed << setprecision(20);
  int n = scan(), m = scan();
  vector<int64_t> a(n + 1);
  for (int i : Rep(n)) {
    int b = scan();
    if (i & 1) b = -b;
    a[i] += b;
    a[i + 1] -= b;
  }
  dsu d(n + 1);
  while (m--) {
    int l = scan() - 1, r = scan();
    tie(l, r) = d.unite(l, r);
    if (r != -1) a[l] += a[r];
  }
  for (int i : Rep(n + 1))
    if (d.root(i) == i) {
      if (a[i]) {
        cout << "NO\n";
        exit(0);
      }
    }
  cout << "YES\n";
}