#include <iostream>
#include <vector>
using namespace std;
#define oo 1000000000
int main() {
int n, x; cin >> n >> x;
vector<int> v(n);
for (int i = 0; i < n; ++i) {
cin >> v[i];
}
int sz = 1;
vector<int> dp(n);
vector<int> c(n+1, oo);
c[0] = 0;
c[1] = v[0];
dp[0] = 1;
for (int i = 1; i < n; ++i) {
if (v[i] < c[1]) c[1] = v[i], dp[i] = 1;
else if (v[i] > c[sz]) c[sz+1] = v[i], dp[i] = ++sz;
else {
int k = lower_bound(c.begin(), c.end(), v[i]) - c.begin();
c[k] = v[i];
dp[i] = k;
}
}
vector<int> sufdp(n);
c.assign(0, n+1);
c[0] = oo;
c[1] = v[n-1] + x;
dp[n-1] = 1;
sz = 1;
int ans = dp[n-1];
for (int i = n-2; i >= 0; --i){
if (v[i] > c[1]) ans = max(ans, dp[i]);
else if (v[i] < c[sz]) ans = max(ans, dp[i] + sz);
else{
int k = upper_bound(c.begin(), c.end(), v[i]) - c.begin() - 1;
ans = max(ans, dp[i] + k - 1);
}
if (v[i] + x > c[1]) c[1] = v[i] + x, dp[i] = 1;
else if (v[i] + x < c[sz]) c[sz+1] = v[i] + x, dp[i] = ++sz;
else{
int k = upper_bound(c.begin(), c.end(), v[i] + x) - c.begin() - 1;
c[k] = v[i] + x;
dp[i] = k;
}
}
cout << ans << "\n";
return 0;
}
Compilation message
glo.cpp: In function 'int main()':
glo.cpp:45:21: error: 'upper_bound' was not declared in this scope
45 | int k = upper_bound(c.begin(), c.end(), v[i]) - c.begin() - 1;
| ^~~~~~~~~~~
glo.cpp:52:21: error: 'upper_bound' was not declared in this scope
52 | int k = upper_bound(c.begin(), c.end(), v[i] + x) - c.begin() - 1;
| ^~~~~~~~~~~
