#include<cstdio>
#include<set>
using namespace std;
constexpr int maxn = 1e5+10, logn = 20;
struct BIT
{
int bit[maxn];
void upd(int x, int v) {
for(; x < maxn; x += x&-x)
bit[x] += v;
}
int query(int x) {
int ans = 0;
for(; x > 0; x -= x&-x)
ans += bit[x];
return ans;
}
int bs(int v) {
int pos = 0, st = v;
for(int l = logn; l >= 0; l--) {
if(pos + (1 << l) >= maxn) continue;
if(bit[pos + (1 << l)] < v) {
pos += (1 << l);
v -= bit[pos];
}
}
return pos+(st>0);
}
} bit;
struct SegmentTree
{
int tree[4*maxn], a[maxn];
void build(int node, int i, int j) {
if(i == j) return (void)(tree[node] = a[i]);
int m = (i+j) >> 1;
build(2*node, i, m); build(2*node+1, m+1, j);
tree[node] = max(tree[2*node], tree[2*node+1]);
}
int query(int node, int i, int j, int l, int r) {
if(i > r || j < l) return 0;
if(i >= l && j <= r) return tree[node];
int m = (i+j) >> 1;
return max(query(2*node, i, m, l, r), query(2*node+1, m+1, j, l, r));
}
} seg;
int s[maxn], e[maxn], pref[maxn];
int GetBestPosition(int N, int C, int R, int *K, int *S, int *E) {
set<int> st;
for(int i = 1; i <= N; i++)
bit.upd(i, 1), st.insert(i), seg.a[i] = K[i-1];
seg.build(1, 1, N-1);
for(int i = 0; i < C; i++) {
++E[i], ++S[i];
s[i] = bit.bs(S[i]-1) + 1;
e[i] = bit.bs(E[i]);
auto it = st.lower_bound(s[i]);
while(next(it) != st.end() && *next(it) <= e[i])
bit.upd(*it, -1), it = st.erase(it);
int v = seg.query(1, 1, N-1, s[i], e[i]-1);
if(v < R) ++pref[s[i]], --pref[e[i]+1];
}
int ans = 0;
for(int i = 1; i <= N; i++) {
pref[i] += pref[i-1];
if(pref[ans] < pref[i])
ans = i;
}
return max(0, ans-1);
}
Compilation message
/usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/crt1.o: In function `_start':
(.text+0x20): undefined reference to `main'
collect2: error: ld returned 1 exit status
