上帝造题的七分钟 2 / 花神游历各国
2024年12月25日大约 2 分钟
lazy 标记是否还要开方
#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN = 100000;
int n, m, a[MAXN + 5];
int t[MAXN * 4 + 5];
bool lazy[MAXN * 4 + 5]; // 是否还需要开方
// 当前节点为 now,对应的线段为 [l,r]
void build(int now, int l, int r)
{
lazy[now] = true;
if (l == r)
{
t[now] = a[l];
return;
}
int mid = (l + r) / 2;
build(now * 2, l, mid);
build(now * 2 + 1, mid + 1, r);
t[now] = t[now * 2] + t[now * 2 + 1];
}
// 做到了 now 节点,对应区间为 [l,r]
// 单点修改:a[x]~a[y] 开方
void update(int now, int l, int r, int x, int y)
{
if (lazy[now] == false)
return;
if (l == r)
{
t[now] = sqrt(t[now]);
if (t[now] <= 1)
lazy[now] = false;
}
else
{
int mid = (l + r) / 2;
if (x <= mid)
update(now * 2, l, mid, x, y);
if (y >= mid + 1)
update(now * 2 + 1, mid + 1, r, x, y);
t[now] = t[now * 2] + t[now * 2 + 1];
lazy[now] = lazy[now * 2] || lazy[now * 2 + 1];
}
}
int query(int now, int l, int r, int x, int y)
{
if (x <= l && r <= y)
return t[now];
int mid = (l + r) / 2;
int res = 0;
if (x <= mid)
res += query(now * 2, l, mid, x, y);
if (y >= mid + 1)
res += query(now * 2 + 1, mid + 1, r, x, y);
return res;
}
signed main()
{
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n;
for (int i = 1; i <= n; i++)
cin >> a[i];
build(1, 1, n);
cin >> m;
while (m--)
{
int op, x, y, z;
cin >> op;
if (op == 0)
{
cin >> x >> y;
if (x > y)
swap(x, y);
update(1, 1, n, x, y);
}
else
{
cin >> x >> y;
if (x > y)
swap(x, y);
cout << query(1, 1, n, x, y) << "\n";
}
}
return 0;
}
用区间和判断
这题的数不会变为 0,所以不需要开方的条件就是区间和等于区间长度(全都是 1)
#include <bits/stdc++.h>
#define int long long
using namespace std;
const int MAXN = 100000;
int n, m, a[MAXN + 5];
int t[MAXN * 4 + 5];
int lazy[MAXN * 4 + 5];
void build(int now, int l, int r)
{
if (l == r)
{
t[now] = a[l];
return;
}
int mid = (l + r) / 2;
build(now * 2, l, mid);
build(now * 2 + 1, mid + 1, r);
t[now] = t[now * 2] + t[now * 2 + 1];
}
void update(int now, int l, int r, int x, int y, int z)
{
if (t[now] == r - l + 1)
return;
if (l == r)
{
t[now] = sqrt(t[now]);
return;
}
int mid = (l + r) / 2;
if (x <= mid)
update(now * 2, l, mid, x, y, z);
if (y >= mid + 1)
update(now * 2 + 1, mid + 1, r, x, y, z);
t[now] = t[now * 2] + t[now * 2 + 1];
}
int query(int now, int l, int r, int x, int y)
{
if (x <= l && r <= y)
return t[now];
int mid = (l + r) / 2;
int res = 0;
if (x <= mid)
res += query(now * 2, l, mid, x, y);
if (y >= mid + 1)
res += query(now * 2 + 1, mid + 1, r, x, y);
return res;
}
signed main()
{
ios::sync_with_stdio(false);
cin.tie(0);
cin >> n;
for (int i = 1; i <= n; i++)
cin >> a[i];
build(1, 1, n);
cin >> m;
while (m--)
{
int op, x, y, z;
cin >> op;
if (op == 0)
{
cin >> x >> y;
if (x > y)
swap(x, y);
update(1, 1, n, x, y, z);
}
else
{
cin >> x >> y;
if (x > y)
swap(x, y);
cout << query(1, 1, n, x, y) << "\n";
}
}
return 0;
}