#include <bits/stdc++.h>
using namespace std;
const int maxn = 200005;
int n, q;
int a[maxn];
long long delta[maxn];
bool is_diff(long long x, long long y)
{
if (x > 0 && y < 0)
{
return true;
}
if (x < 0 && y > 0)
{
return true;
}
return false;
}
struct segment_tree
{
struct state
{
int first;
int last;
long long dp[2][2];
state()
{
first = 0;
last = 0;
for (int i = 0; i <= 1; ++i)
{
for (int j = 0; j <= 1; ++j)
{
dp[i][j] = 0;
}
}
}
};
state tree[4 * maxn];
state combine(const state& left_child, const state& right_child)
{
state result;
result.first = left_child.first;
result.last = right_child.last;
for (int first_l = 0; first_l <= 1; ++first_l)
{
for (int last_l = 0; last_l <= 1; ++last_l)
{
for (int first_r = 0; first_r <= 1; ++first_r)
{
for (int last_r = 0; last_r <= 1; ++last_r)
{
if (last_l == 1 && first_r == 1)
{
if (is_diff(left_child.last, right_child.first) == false)
{
result.dp[first_l][last_r] = max(result.dp[first_l][last_r], left_child.dp[first_l][last_l] + right_child.dp[first_r][last_r]);
}
}
else
{
result.dp[first_l][last_r] = max(result.dp[first_l][last_r], left_child.dp[first_l][last_l] + right_child.dp[first_r][last_r]);
}
}
}
}
}
return result;
}
void build(int node, int l, int r)
{
if (l == r)
{
tree[node].first = delta[l];
tree[node].last = delta[l];
tree[node].dp[0][0] = 0;
tree[node].dp[0][1] = 0;
tree[node].dp[1][0] = 0;
tree[node].dp[1][1] = abs(delta[l]);
return;
}
int mid = (l + r) / 2;
build(2 * node, l, mid);
build(2 * node + 1, mid + 1, r);
tree[node] = combine(tree[2 * node], tree[2 * node + 1]);
}
void update(int node, int l, int r, int pos, long long val)
{
if (l == r)
{
tree[node].first = val;
tree[node].last = val;
tree[node].dp[0][0] = 0;
tree[node].dp[0][1] = 0;
tree[node].dp[1][0] = 0;
tree[node].dp[1][1] = abs(val);
return;
}
int mid = (l + r) / 2;
if (pos <= mid)
{
update(2 * node, l, mid, pos, val);
}
else
{
update(2 * node + 1, mid + 1, r, pos, val);
}
tree[node] = combine(tree[2 * node], tree[2 * node + 1]);
}
void update(int pos, long long val)
{
update(1, 1, n - 1, pos, val);
}
void build()
{
build(1, 1, n - 1);
}
};
segment_tree tree;
void fastIO()
{
ios_base::sync_with_stdio(0);
cin.tie(0);
cout.tie(0);
}
int main()
{
fastIO();
cin >> n >> q;
for (int i = 1; i <= n; ++i)
{
cin >> a[i];
}
for (int i = 1; i <= n - 1; ++i)
{
delta[i] = a[i + 1] - a[i];
}
tree.build();
for (int i = 1; i <= q; ++i)
{
int l, r, x;
cin >> l >> r >> x;
if (l != 1)
{
delta[l - 1] += x;
tree.update(l - 1, delta[l - 1]);
}
if (r != n)
{
delta[r] -= x;
tree.update(r, delta[r]);
}
long long ans = 0;
for (int fr = 0; fr <= 1; ++fr)
{
for (int sc = 0; sc <= 1; ++sc)
{
ans = max(ans, tree.tree[1].dp[fr][sc]);
}
}
cout << ans << "\n";
}
return 0;
}
/*
4 3
1 2 3 4
1 2 1
1 1 2
2 3 1
4 1
1 2 3 4
1 2 1
*/
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
13 ms |
31572 KB |
Output is correct |
2 |
Correct |
11 ms |
31572 KB |
Output is correct |
3 |
Correct |
11 ms |
31572 KB |
Output is correct |
4 |
Correct |
11 ms |
31580 KB |
Output is correct |
5 |
Correct |
11 ms |
31552 KB |
Output is correct |
6 |
Correct |
11 ms |
31572 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
13 ms |
31572 KB |
Output is correct |
2 |
Correct |
11 ms |
31572 KB |
Output is correct |
3 |
Correct |
11 ms |
31572 KB |
Output is correct |
4 |
Correct |
11 ms |
31580 KB |
Output is correct |
5 |
Correct |
11 ms |
31552 KB |
Output is correct |
6 |
Correct |
11 ms |
31572 KB |
Output is correct |
7 |
Correct |
15 ms |
31704 KB |
Output is correct |
8 |
Correct |
16 ms |
31684 KB |
Output is correct |
9 |
Correct |
17 ms |
31684 KB |
Output is correct |
10 |
Correct |
16 ms |
31684 KB |
Output is correct |
11 |
Correct |
16 ms |
31700 KB |
Output is correct |
12 |
Correct |
16 ms |
31700 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
13 ms |
31572 KB |
Output is correct |
2 |
Correct |
11 ms |
31572 KB |
Output is correct |
3 |
Correct |
11 ms |
31572 KB |
Output is correct |
4 |
Correct |
11 ms |
31580 KB |
Output is correct |
5 |
Correct |
11 ms |
31552 KB |
Output is correct |
6 |
Correct |
11 ms |
31572 KB |
Output is correct |
7 |
Correct |
15 ms |
31704 KB |
Output is correct |
8 |
Correct |
16 ms |
31684 KB |
Output is correct |
9 |
Correct |
17 ms |
31684 KB |
Output is correct |
10 |
Correct |
16 ms |
31684 KB |
Output is correct |
11 |
Correct |
16 ms |
31700 KB |
Output is correct |
12 |
Correct |
16 ms |
31700 KB |
Output is correct |
13 |
Correct |
511 ms |
40860 KB |
Output is correct |
14 |
Correct |
532 ms |
43116 KB |
Output is correct |
15 |
Correct |
567 ms |
43104 KB |
Output is correct |
16 |
Correct |
577 ms |
43004 KB |
Output is correct |
17 |
Correct |
528 ms |
42892 KB |
Output is correct |
18 |
Correct |
510 ms |
43704 KB |
Output is correct |