#include #define REP(i,n) for (int i=0;i<(n);i++) #define FOR(i,a,b) for (int i=(a);i<(b);i++) #define dump1d_arr(array) REP(i,array.size()) cerr << #array << "[" << (i) << "] ==> " << (array[i]) << endl; #define dump2d_arr(array) REP(i,array.size()) REP(j,array[i].size()) cerr << #array << "[" << (i) << "]" << "[" << (j) << "] ==> " << (array[i][j]) << endl; #define dump(x) cerr << #x << " => " << (x) << endl; #define CLR(vec) { REP(i,vec.size()) vec[i] = 0; } #define loINF (long)10000000000 #define shINF (short)10000 #define SORT(c) sort((c).begin(),(c).end()) using namespace std; typedef vector VI; typedef vector VVI; typedef vector VL; int main(void){ short N,M; cin >> N >> M; VI a(N+1); VVI edge(N+1,VI(0)); REP(i,N) cin >> a[i]; short u,v; REP(i,M){ cin >> u >> v; edge[u].push_back(v); edge[v].push_back(u); } VL low; VL big; short l,b; FOR(i,1,N+1){ l = 0; b = 0; low = VL(0); big = VL(0); REP(j,edge[i].size()){ if (a[edge[i][j]-1] < a[i-1]){ l ++; REP(k,low.size()){ if (low[k] == a[edge[i][j]-1]){ l--; break; } } low.push_back(a[edge[i][j]-1]); } if (a[edge[i][j]-1] > a[i-1]){ b++; REP(k,big.size()){ if (big[k] == a[edge[i][j]-1]){ b--; break; } } big.push_back(a[edge[i][j]-1]); } } if (l >= 2 || b >= 2){ cout << "YES" << endl; exit(0); } } cout << "NO" << endl; return 0; }