Submission #141633

#	Time	Username	Problem	Language	Result	Execution time	Memory
141633		HellAngel	Two Antennas (JOI19_antennas)	C++14	100 / 100	1158 ms	63644 KiB

antennas

#include <bits/stdc++.h>
#define int long long
const int Inf = 1e15;
using namespace std;
const int maxn = 2e5 + 7;
 
int h[maxn], a[maxn], b[maxn], l[maxn], r[maxn], ans[maxn];
int d[4 * maxn], c[maxn], q, n;
vector<int> add[maxn], era[maxn], chk[maxn];
int D[4 * maxn], lz[4 * maxn], C[maxn * 4];
 
void Push_Down(int id, int l, int r)
{
    if(lz[id] != Inf && l < r)
    {
        lz[id * 2] = min(lz[id * 2], lz[id]);
        lz[id * 2 + 1] = min(lz[id * 2 + 1], lz[id]);
        D[id * 2] = max(D[id * 2], C[id * 2] - lz[id * 2]);
        D[id * 2 + 1] = max(D[id * 2 + 1], C[id * 2 + 1] - lz[id * 2 + 1]);
    }
    lz[id] = Inf;
}
 
void Set(int id, int l, int r, int pos, int val)
{
 
    Push_Down(id, l, r);
    if(l == r)
    {
        C[id] = val;
        return;
    }
    Push_Down(id, l, r);
    int mid = l + r >> 1;
    if(pos <= mid) Set(id * 2, l, mid, pos, val);
    else Set(id * 2 + 1, mid + 1, r, pos, val);
    D[id] = max(D[id * 2], D[id * 2 + 1]);
    C[id] = max(C[id * 2], C[id * 2 + 1]);
}
 
void Update(int id, int l, int r, int u, int v, int val)
{
    Push_Down(id, l, r);
    if(l > v || r < u) return;
    if(u <= l && r <= v)
    {
        lz[id] = val;
        D[id] = max(D[id], C[id] - lz[id]);
        return;
    }
    int mid = l + r >> 1;
    Update(id * 2, l, mid, u, v, val);
    Update(id * 2 + 1, mid + 1, r, u, v, val);
    D[id] = max(D[id * 2], D[id * 2 + 1]);
    C[id] = max(C[id * 2], C[id * 2 + 1]);
}
 
int Get(int id, int l, int r, int u, int v)
{
    Push_Down(id, l, r);
    if(l > v || r < u) return -1;
    if(u <= l && r <= v) return D[id];
    int mid = l + r >> 1;
    return max(Get(id * 2, l, mid, u, v), Get(id * 2 + 1, mid + 1, r, u, v));
}
 
void Solve()
{
    for(int i = 0; i < 4 * maxn; i++) lz[i] = Inf, D[i] = C[i] = -Inf;
    for(int i = 1; i <= n + 1; i++) add[i] = era[i] = chk[i] = {};
    for(int i = 1; i <= q; i++) chk[r[i]].push_back(i);
    for(int i = 1; i <= n; i++)
    {
        if(i + a[i] <= n) add[i + a[i]].push_back(i);
        if(i + b[i] + 1 <= n + 1) era[i + b[i] + 1].push_back(i);
    }
    for(int i = 1; i <= n + 1; i++)
    {
        for(auto j: chk[i - 1])
        {
            ans[j] = max(ans[j], Get(1, 1, n, l[j], r[j]));
        }
        if(i == n + 1) return;
        for(auto j: add[i]) Set(1, 1, n, j, h[j]);
        for(auto j: era[i]) Set(1, 1, n, j, -Inf);
        if(i - a[i] >= 1)
        Update(1, 1, n, max(i - b[i], 1ll), i - a[i], h[i]);
    }
}
 
int32_t main()
{
    ios_base::sync_with_stdio(0);
    cin.tie(0);
    if(fopen("test.inp", "r")) freopen("test.inp", "r", stdin), freopen("test.out", "w", stdout);
    fill_n(ans, maxn, -1);
    cin >> n;
    for(int i = 1; i <= n; i++) cin >> h[i] >> a[i] >> b[i];
    cin >> q;
    for(int i = 1; i <= q; i++) cin >> l[i] >> r[i];
    Solve();
    reverse(h + 1, h + n + 1);
    reverse(a + 1, a + n + 1);
    reverse(b + 1, b + n + 1);
    for(int i = 1; i <= q; i++)
    {
        l[i] = n + 1 - l[i];
        r[i] = n + 1 - r[i];
        swap(l[i], r[i]);
    }
    Solve();
    for(int i = 1; i <= q; i++) cout << ans[i] << '\n';
}

Compilation message (stderr)

antennas.cpp: In function 'void Set(long long int, long long int, long long int, long long int, long long int)':
antennas.cpp:34:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid = l + r >> 1;
               ~~^~~
antennas.cpp: In function 'void Update(long long int, long long int, long long int, long long int, long long int, long long int)':
antennas.cpp:51:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid = l + r >> 1;
               ~~^~~
antennas.cpp: In function 'long long int Get(long long int, long long int, long long int, long long int, long long int)':
antennas.cpp:63:17: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
     int mid = l + r >> 1;
               ~~^~~
antennas.cpp: In function 'int32_t main()':
antennas.cpp:95:63: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]
     if(fopen("test.inp", "r")) freopen("test.inp", "r", stdin), freopen("test.out", "w", stdout);
                                ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
antennas.cpp:95:63: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)', declared with attribute warn_unused_result [-Wunused-result]

• Subtask 1: 2 / 2
• Subtask 2: 11 / 11
• Subtask 3: 22 / 22
• Subtask 4: 65 / 65