#line 2 "/home/sakflat/CP/_library/cpp/template/template.cpp" //yukicoder@cpp17 #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include using namespace std; using ll = long long; using P = pair; const ll MOD = 998244353; const ll MODx = 1000000007; const int INF = (1<<30)-1; const ll LINF = (1LL<<62LL)-1; const double EPS = (1e-10); P ar4[4] = {{0,1},{0,-1},{1,0},{-1,0}}; P ar8[8] = {{-1,-1},{-1,0},{-1,1},{0,-1},{0,1},{1,-1},{1,0},{1,1}}; template vector make_vector(size_t a, T b) { return vector(a, b); } template auto make_vector(size_t a, Ts... ts) { return vector(a, make_vector(ts...)); } /* 確認ポイント cout << fixed << setprecision(n) << 小数計算//n桁の小数表記になる 計算量は変わらないが楽できるシリーズ min(max)_element(iter,iter)で一番小さい(大きい)値のポインタが帰ってくる count(iter,iter,int)でintがiterからiterの間にいくつあったかを取得できる */ /* comment outed because can cause bugs __attribute__((constructor)) void initial() { cin.tie(0); ios::sync_with_stdio(false); } */ #line 2 "/home/sakflat/CP/_library/cpp/template/basic.cpp" int main(){ int n,m;cin>>n>>m; vector A(n); for(int i = 0; n > i; i++)cin>>A[i]; vector> B(n, vector()); for(int i = 0; m > i; i++){ int x,y;cin>>x>>y;x--;y--; B[x].push_back(y); B[y].push_back(x); } for(int i = 0; n > i; i++){ if(B[i].size() <= 1)continue; int dec = -1; int gre = -1; for(int j = 0; m > j; j++){ if(A[B[i][j]] < A[i]){ if(dec == -1){ dec = A[B[i][j]]; }else if(dec != A[B[i][j]]){ cout << "YES" << endl; return 0; } }else if(A[B[i][j]] > A[i]){ if(gre == -1){ gre = A[B[i][j]]; }else if(gre != A[B[i][j]]){ cout << "YES" << endl; return 0; } } } } cout << "NO" << endl; return 0; }