#include //#include using namespace std; //using namespace atcoder; //using mint = modint1000000007; //const int mod = 1000000007; //using mint = modint998244353; //const int mod = 998244353; //const int INF = 1e9; const long long LINF = 1e18; #define rep(i, n) for (int i = 0; i < (n); ++i) #define rep2(i,l,r)for(int i=(l);i<(r);++i) #define rrep(i, n) for (int i = (n-1); i >= 0; --i) #define rrep2(i,l,r)for(int i=(r-1);i>=(l);--i) #define all(x) (x).begin(),(x).end() #define allR(x) (x).rbegin(),(x).rend() #define endl "\n" #define P pair template inline bool chmax(A & a, const B & b) { if (a < b) { a = b; return true; } return false; } template inline bool chmin(A & a, const B & b) { if (a > b) { a = b; return true; } return false; } struct Edge { int to; long long cost; Edge(int _to, long long _cost) :to(_to), cost(_cost) {} }; int main() { ios::sync_with_stdio(false); cin.tie(nullptr); int n, m; cin >> n >> m; vectorh(n); vector>g0(n), g1(n); rep(i, n)cin >> h[i]; rep(i, m) { int x, y; cin >> x >> y; x--, y--; if (x > y)swap(x, y); g0[x].emplace_back(y, max(0, h[y] - h[x])); g1[y].emplace_back(x, max(0, h[x] - h[y])); } { vector> dp(n, vector(2, -1)); dp[0][1] = 0; rep(i, n)rep(j, 2) { if (-1 == dp[i][j])continue; for (Edge e : g0[i]) { long long nval = dp[i][j] + e.cost; int npos = e.to; if (0 == j) { if (e.cost < 0) chmax(dp[npos][1], nval); } else { if (e.cost > 0) chmax(dp[npos][0], nval); else chmax(dp[npos][1], nval); } } } cout << max(dp[n - 1][0], dp[n - 1][1]) << endl; } { vector> dp(n, vector(2, -1)); dp[n - 1][1] = 0; rrep(i, n)rep(j, 2) { if (-1 == dp[i][j])continue; for (Edge e : g1[i]) { long long nval = dp[i][j] + e.cost; int npos = e.to; if (0 == j) { if (e.cost < 0) chmax(dp[npos][1], nval); } else { if (e.cost > 0) chmax(dp[npos][0], nval); else chmax(dp[npos][1], nval); } } } cout << max(dp[0][0], dp[0][1]) << endl; } return 0; }