#include <bits/stdc++.h> #define MASK(i) (1LL << (i)) #define BIT(x, i) (((x) >> (i)) & 1) #define ii pair<int, int> #define fi first #define se second #define all(v) begin(v), end(v) #define siz(v) (int)(v).size() using namespace std; const int MAXN = 2e5 + 4, mod = 1e9 + 7, MAXB = 20; template<class X, class Y> bool minimize(X &x, const Y &y){return x > y ? x = y, 1: 0;} template<class X, class Y> bool maximize(X &x, const Y &y){return x < y ? x = y, 1: 0;} void add(int &a, const int &b){ a += b; if (a >= mod) a -= mod; } void sub(int &a, const int &b){ a -= b; if (a < 0) a += mod; } int mul(const int &a, const int &b){ return 1LL * a * 1LL * b % mod; } int numVal, maxDelta, val[MAXN], pre[MAXN], suff[MAXN]; vector<int> compress; struct fenwickTree{ int n; vector<int> bit; fenwickTree(int _n = 0): n(_n){ bit.assign(n + 1, 0); } void update(int pos, const int &val, bool inc){ if (!inc){ for(; pos <= n; pos += pos & -pos) maximize(bit[pos], val); }else{ for(; pos > 0; pos ^= pos & -pos) maximize(bit[pos], val); } } int get(int pos, bool inc){ int best = 0; if (!inc){ for(; pos > 0; pos ^= pos & -pos) maximize(best, bit[pos]); }else{ for(; pos <= n; pos += pos & -pos) maximize(best, bit[pos]); } return best; } }; int getPos(const int &pos){ return lower_bound(all(compress), pos) - begin(compress) + 1; } void input(){ cin >> numVal >> maxDelta; for(int i = 1; i <= numVal; i++) cin >> val[i]; } void solve(){ for(int i = 1; i <= numVal; i++){ compress.push_back(val[i]); compress.push_back(val[i] - maxDelta); } sort(all(compress)); compress.resize(unique(all(compress)) - begin(compress)); fenwickTree myBit(siz(compress)); for(int i = 1; i <= numVal; i++){ pre[i] = myBit.get(getPos(val[i] - maxDelta) - 1, 0) + 1; myBit.update(getPos(val[i] - maxDelta), pre[i], 0); } int res = 0; myBit = fenwickTree(siz(compress)); for(int i = numVal; i >= 1; i--){ maximize(res, pre[i] + myBit.get(getPos(val[i] - maxDelta) + 1, 1)); suff[i] = myBit.get(getPos(val[i]) + 1, 1) + 1; myBit.update(getPos(val[i]), suff[i], 1); } cout << res << '\n'; } int main(){ ios_base::sync_with_stdio(0); cin.tie(0); cout.tie(0); #define task "test" if (fopen(task".inp", "r")){ freopen(task".inp", "r", stdin); freopen(task".out", "w", stdout); } input(); solve(); }

glo.cpp: In function 'int main()':
glo.cpp:100:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  100 |         freopen(task".inp", "r", stdin);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~
glo.cpp:101:16: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
  101 |         freopen(task".out", "w", stdout);
      |         ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~