#include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; typedef long long ll; typedef unsigned int ui; const ll mod = 1000000007; const ll INF = (ll)1000000007 * 1000000007; typedef pair P; #define stop char nyaa;cin>>nyaa; #define rep(i,n) for(int i=0;i=0;i--) #define Rep(i,sta,n) for(int i=sta;i=sta;i--) #define rep1(i,n) for(int i=1;i<=n;i++) #define per1(i,n) for(int i=n;i>=1;i--) #define Rep1(i,sta,n) for(int i=sta;i<=n;i++) typedef long double ld; const ld eps = 1e-8; const ld pi = acos(-1.0); typedef pair LP; int dx[4]={1,-1,0,0}; int dy[4]={0,0,1,-1}; templatebool chmax(T &a, const T &b) {if(abool chmin(T &a, const T &b) {if(b struct LazySegmentTree {// (*composition)は前が新たな作用素 public: LazySegmentTree() : LazySegmentTree(0) {} LazySegmentTree(int n) : LazySegmentTree(std::vector(n, e())) {} LazySegmentTree(const std::vector& v) : _n(int(v.size())) { log = ceil_pow2(_n); size = 1 << log; d = std::vector(2 * size, e()); lz = std::vector(size, id()); for (int i = 0; i < _n; i++) d[size + i] = v[i]; for (int i = size - 1; i >= 1; i--) { update_(i); } } void set(int p, S x) { assert(0 <= p && p < _n); p += size; for (int i = log; i >= 1; i--) push(p >> i); d[p] = x; for (int i = 1; i <= log; i++) update_(p >> i); } S get(int p) { assert(0 <= p && p < _n); p += size; for (int i = log; i >= 1; i--) push(p >> i); return d[p]; } S query(int l, int r) { assert(0 <= l && l <= r && r <= _n); if (l == r) return e(); l += size; r += size; for (int i = log; i >= 1; i--) { if (((l >> i) << i) != l) push(l >> i); if (((r >> i) << i) != r) push(r >> i); } S sml = e(), smr = e(); while (l < r) { if (l & 1) sml = op(sml, d[l++]); if (r & 1) smr = op(d[--r], smr); l >>= 1; r >>= 1; } return op(sml, smr); } S all_query() { return d[1]; } void update(int p, F f) { assert(0 <= p && p < _n); p += size; for (int i = log; i >= 1; i--) push(p >> i); d[p] = mapping(f, d[p]); for (int i = 1; i <= log; i++) update_(p >> i); } void update(int l, int r, F f) { assert(0 <= l && l <= r && r <= _n); if (l == r) return; l += size; r += size; for (int i = log; i >= 1; i--) { if (((l >> i) << i) != l) push(l >> i); if (((r >> i) << i) != r) push((r - 1) >> i); } { int l2 = l, r2 = r; while (l < r) { if (l & 1) all_apply(l++, f); if (r & 1) all_apply(--r, f); l >>= 1; r >>= 1; } l = l2; r = r2; } for (int i = 1; i <= log; i++) { if (((l >> i) << i) != l) update_(l >> i); if (((r >> i) << i) != r) update_((r - 1) >> i); } } template int max_right(int l) { return max_right(l, [](S x) { return g(x); }); } template int max_right(int l, G g) { assert(0 <= l && l <= _n); assert(g(e())); if (l == _n) return _n; l += size; for (int i = log; i >= 1; i--) push(l >> i); S sm = e(); do { while (l % 2 == 0) l >>= 1; if (!g(op(sm, d[l]))) { while (l < size) { push(l); l = (2 * l); if (g(op(sm, d[l]))) { sm = op(sm, d[l]); l++; } } return l - size; } sm = op(sm, d[l]); l++; } while ((l & -l) != l); return _n; } template int min_left(int r) { return min_left(r, [](S x) { return g(x); }); } template int min_left(int r, G g) { assert(0 <= r && r <= _n); assert(g(e())); if (r == 0) return 0; r += size; for (int i = log; i >= 1; i--) push((r - 1) >> i); S sm = e(); do { r--; while (r > 1 && (r % 2)) r >>= 1; if (!g(op(d[r], sm))) { while (r < size) { push(r); r = (2 * r + 1); if (g(op(d[r], sm))) { sm = op(d[r], sm); r--; } } return r + 1 - size; } sm = op(d[r], sm); } while ((r & -r) != r); return 0; } private: int _n, size, log; std::vector d; std::vector lz; void update_(int k) { d[k] = op(d[2 * k], d[2 * k + 1]); } void all_apply(int k, F f) { d[k] = mapping(f, d[k]); if (k < size) lz[k] = composition(f, lz[k]); } void push(int k) { all_apply(2 * k, lz[k]); all_apply(2 * k + 1, lz[k]); lz[k] = id(); } int ceil_pow2(int n) { int x = 0; while ((1U << x) < (unsigned int)(n)) x++; return x; } }; int n,m; int b[200010],l[200010],r[200010]; set se[200010]; int f(int a,int b){return min(a,b);} int e(){return 0;} int g(int a,int b){return a+b;} int id(){return 0;} void solve(){ cin >> n >> m; rep(i,n) cin >> b[i]; rep(i,m){ cin >> l[i] >> r[i]; l[i]-=1; se[l[i]].insert(r[i]); } LazySegmentTree segs[2]={LazySegmentTree(n-n/2),LazySegmentTree(n/2)}; rep(i,n){ if(!se[i].empty()) { int r=*se[i].begin(); int z=b[i]-segs[i%2].get(i/2); if(i%2==r%2){ segs[i%2].update(i/2,r/2,z); segs[1-i%2].update((i+1)/2,(r+1)/2,-z); } else{ segs[i%2].update(i/2,(r+1)/2,z); segs[1-i%2].update((i+1)/2,r/2,-z); } se[i].erase(se[i].begin()); if(se[i].size()>se[r].size()) swap(se[i],se[r]); for(int t:se[i]){ se[r].insert(t); } } } rep(i,n){ if(segs[i%2].get(i/2)!=b[i]){ cout << "NO" << endl; return; } } cout << "YES" << endl; } int main(){ ios::sync_with_stdio(false); cin.tie(0); cout << fixed << setprecision(50); solve(); }