#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
constexpr int INF1 = 1e9 + 100;
int n;
int a[250250];
int go[250250], sp[250250][20];
ll S[250250];
struct Node{
array<int, 2> f[51];
int pos, sz;
Node(){}
Node(int _pos, int nxt){
f[0] = {nxt, 1};
pos = _pos;
sz = 1;
}
};
array<int, 2> operator + (const array<int, 2> &x, int y){
return {x[0], x[1]+y};
}
void merge(Node &P, const Node &L, const Node &R){
P.sz = 0;
for (int i=0;i<L.sz;i++){
if (L.f[i][0] >= R.pos + R.sz) P.f[P.sz++] = L.f[i];
else P.f[P.sz++] = R.f[L.f[i][0]-R.pos] + L.f[i][1];
}
for (int i=0;i<R.sz;i++){
if (P.sz==51) return;
P.f[P.sz++] = R.f[i];
}
}
void push(Node &L, const Node &R){
for (int i=0;i<L.sz;i++) if (L.f[i][0] < R.pos + R.sz) L.f[i] = R.f[L.f[i][0]-R.pos] + L.f[i][1];
for (int i=0;i<R.sz;i++){
if (L.sz==51) return;
L.f[L.sz++] = R.f[i];
}
}
struct Seg{
Node tree[1101000], ret;
void init(int i, int l, int r){
if (l==r) {tree[i] = Node(l, go[l]); return;}
int m = (l+r)>>1;
init(i<<1, l, m); init(i<<1|1, m+1, r);
tree[i].pos = l;
merge(tree[i], tree[i<<1], tree[i<<1|1]);
}
void update(int i, int l, int r, int s, int e){
if (r<s || e<l) return;
if (l==r){
tree[i] = Node(l, go[l]);
return;
}
int m = (l+r)>>1;
update(i<<1, l, m, s, e); update(i<<1|1, m+1, r, s, e);
merge(tree[i], tree[i<<1], tree[i<<1|1]);
}
void query(int i, int l, int r, int s, int e){
if (r<s || e<l) return;
if (s<=l && r<=e){
push(ret, tree[i]);
return;
}
int m = (l+r)>>1;
query(i<<1, l, m, s, e); query(i<<1|1, m+1, r, s, e);
}
}tree;
void init(int n){
for (int i=1;i<=n;i++) S[i] = S[i-1] + a[i];
go[n+1] = n+1;
for (int i=1;i<=n;i++){
go[i] = n+1;
for (int j=i+2;j<=min(i+50, n);j++) if (S[j-1] - S[i] > max(a[i], a[j])){
go[i] = j;
break;
}
}
for (int i=n;i;i--) go[i] = min(go[i], go[i+1]);
tree.init(1, 1, n);
// for (int i=n;i;i--) assert(go[i] - i <= 50);
// for (int i=1;i<=n+1;i++) sp[i][0] = go[i];
// for (int j=1;j<20;j++){
// for (int i=1;i<=n+1;i++) sp[i][j] = sp[sp[i][j-1]][j-1];
// }
}
int solve(int l, int r){
if (r-l+1 < 3) return -INF1;
int cnt = 0;
tree.ret.sz = 0;
tree.ret.pos = l;
for (int i=0;i<tree.ret.sz;i++) cnt = max(cnt, tree.ret.f[i][1]-1);
return cnt * 2 + 1;
}
int query(int l, int r){
int ret = 1;
if (l==r) return ret;
if (S[r-1]-S[l-1] > a[r]) ret = 2;
if (S[r]-S[l] > a[l]) ret = 2;
int nl = r+1, nr = l-1;
for (int i=l+1;i<=min(l+30, r);i++) if (S[i-1]-S[l-1] > a[i]) {nl = i; break;}
for (int i=r-1;i>=max(l, r-30);i--) if (S[r]-S[i] > a[i]) {nr = i; break;}
if (nl <= nr) ret = 3;
return max({ret, solve(l, r), solve(nl, r) + 1, solve(l, nr) + 1, solve(nl, nr) + 2});
}
int prv[250250];
void update(int x, int y){
a[x] = y;
for (int i=1;i<=n+1;i++) prv[i] = go[i];
init(n);
for (int i=1;i<=n+1;i++) if (prv[i]!=go[i]) assert(x-50 <= i && i <= x);
}
int main(){
scanf("%d", &n);
for (int i=1;i<=n;i++) scanf("%d", a+i);
init(n);
int q;
scanf("%d", &q);
while(q--){
int x, y, l, r;
scanf("%d %d %d %d", &x, &y, &l, &r);
if (a[x]!=y) update(x, y);
l++;
printf("%d\n", query(l, r));
}
}
Compilation message
mizuyokan2.cpp: In function 'int main()':
mizuyokan2.cpp:148:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
148 | scanf("%d", &n);
| ~~~~~^~~~~~~~~~
mizuyokan2.cpp:149:30: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
149 | for (int i=1;i<=n;i++) scanf("%d", a+i);
| ~~~~~^~~~~~~~~~~
mizuyokan2.cpp:154:7: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
154 | scanf("%d", &q);
| ~~~~~^~~~~~~~~~
mizuyokan2.cpp:157:8: warning: ignoring return value of 'int scanf(const char*, ...)' declared with attribute 'warn_unused_result' [-Wunused-result]
157 | scanf("%d %d %d %d", &x, &y, &l, &r);
| ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Incorrect |
87 ms |
220672 KB |
Output isn't correct |
3 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Execution timed out |
4035 ms |
221028 KB |
Time limit exceeded |
4 |
Halted |
0 ms |
0 KB |
- |
# |
결과 |
실행 시간 |
메모리 |
Grader output |
1 |
Correct |
1 ms |
4444 KB |
Output is correct |
2 |
Correct |
1 ms |
4444 KB |
Output is correct |
3 |
Incorrect |
1 ms |
4444 KB |
Output isn't correct |
4 |
Halted |
0 ms |
0 KB |
- |