#include #include #define rep(i,b) for(int i=0;i=0;i--) #define rep1(i,b) for(int i=1;i using mpq = priority_queue, greater>; template bool chmax(T &a, const T &b) { if (a bool chmin(T &a, const T &b) { if (b ll sumv(const vector&a){ll res(0);for(auto&&x:a)res+=x;return res;} bool yn(bool a) { if(a) {cout << "Yes" << endl; return 1;} else {cout << "No" << endl; return 0;}} #define dame { cout << "No" << endl; return 0;} #define dame1 { cout << -1 << endl; return 0;} #define test(x) cout << "test" << x << endl; #define deb(x,y) cout << x << " " << y << endl; #define deb3(x,y,z) cout << x << " " << y << " " << z << endl; #define deb4(x,y,z,x2) cout << x << " " << y << " " << z << " " << x2 << endl; #define out cout << ans << endl; #define outv fore(yans , ans) cout << yans << "\n"; #define show(x) cerr<<#x<<" = "<; using pil = pair; using pli = pair; using pii = pair; using tp = tuple; using vi = vector; using vl = vector; using vs = vector; using vb = vector; using vpii = vector; using vpli = vector; using vpll = vector; using vpil = vector; using vvi = vector>; using vvl = vector>; using vvs = vector>; using vvb = vector>; using vvpii = vector>; using vvpli = vector>; using vvpll = vector; using vvpil = vector; using mint = modint998244353; using vm = vector; using vvm = vector>; vector dx={1,0,-1,0,1,1,-1,-1},dy={0,1,0,-1,1,-1,1,-1}; ll gcd(ll a, ll b) { return a?gcd(b%a,a):b;} ll lcm(ll a, ll b) { return a/gcd(a,b)*b;} const double eps = 1e-10; const ll LINF = 1001002003004005006ll; const int INF = 1001001001; int main(){ int h,w; cin>>h>>w; vvl a(h,vl(w)); rep(i,h){ rep(j,w) cin>>a[i][j]; } vector dp(2,vvl(h,vl(w))); dp[0][0][0] = a[0][0]; bool ok = false; rep(i,h){ rep(j,w){ rep(kk,2){ int x,y; x = i + dx[kk]; y = j + dy[kk]; if (x <= h-1 && x >= 0 && y <= w-1 && y >= 0){ if (dp[0][i][j]){ if (dp[0][i][j] > a[x][y]){ chmax(dp[0][x][y] , dp[0][i][j] + a[x][y]); if (x == h-1 && y == w-1) ok = true; }else{ chmax(dp[1][x][y] , dp[0][i][j]); } } if (dp[1][i][j]){ if (dp[1][i][j] > a[x][y]){ if (x == h-1 && y == w-1) ok = true; chmax(dp[1][x][y] , dp[1][i][j] + a[x][y]); } } } } } } yn(ok); return 0; }