Submission #797434

#	Time	Username	Problem	Language	Result	Execution time	Memory
797434		Sam_a17	Homecoming (BOI18_homecoming)	C++17	0 / 100	295 ms	188164 KiB

homecoming

#define _CRT_SECURE_NO_WARNINGS
#include <bits/stdc++.h>
// #include <atcoder/all>
#include <cstdio>
using namespace std;
 
#ifndef ONLINE_JUDGE
#define dbg(x) cerr << #x <<" "; print(x); cerr << endl;
#else
#define dbg(x)
#endif
 
#define sz(x) (int((x).size()))
#define len(x) (int)x.length()
#define all(x) (x).begin(), (x).end()
#define rall(x) (x).rbegin(), (x).rend()
#define clr(x) (x).clear()
#define blt(x) __builtin_popcount(x)
#define uniq(x) x.resize(unique(all(x)) - x.begin());
 
#define pb push_back
#define popf pop_front
#define popb pop_back
#define ld long double
#define ll long long
 
void print(long long t) {cerr << t;}
void print(int t) {cerr << t;}
void print(string t) {cerr << t;}
void print(char t) {cerr << t;}
void print(double t) {cerr << t;}
void print(unsigned long long t) {cerr << t;}
void print(long double t) {cerr << t;}
 
template <class T, class V> void print(pair <T, V> p);
template <class T> void print(vector <T> v);
template <class T> void print(set <T> v);
template <class T, class V> void print(map <T, V> v);
template <class T> void print(multiset <T> v);
template <class T> void print(T v[],T n) {cerr << "["; for(int i = 0; i < n; i++) {cerr << v[i] << " ";} cerr << "]";}
template <class T, class V> void print(pair <T, V> p) {cerr << "{"; print(p.first); cerr << ","; print(p.second); cerr << "}";}
template <class T> void print(vector <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(deque <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(set <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T> void print(multiset <T> v) {cerr << "[ "; for (T i : v) {print(i); cerr << " ";} cerr << "]";}
template <class T, class V> void print(map <T, V> v) {cerr << "[ "; for (auto i : v) {print(i); cerr << " ";} cerr << "]";}
 
#include <ext/pb_ds/assoc_container.hpp>
using namespace __gnu_pbds;
#define nl '\n'
 
// for random generations
mt19937 myrand(chrono::steady_clock::now().time_since_epoch().count());
// mt19937 myrand(131);
 
// for grid problems
int dx[8] = {1,0,-1,0,1,-1,1,-1};
int dy[8] = {0,1,0,-1,1,1,-1,-1};
char ch[4] = {'v', '>', '^', '<'};
 
long long ka() {
    long long x = 0;
    bool z = false;
    while (1)
    {
        char y = getchar();
        if (y == '-')
            z = true;
        else if ('0' <= y && y <= '9')
            x = x * 10 + y - '0';
        else
        {
            if (z)
                x *= -1;
            return x;
        }
    }
}
 
// lowest / (1 << 17) >= 1e5 / (1 << 18) >= 2e5 / (1 << 21) >= 1e6
void fastIO() {
  ios_base::sync_with_stdio(false);
  cin.tie(nullptr); cout.tie(nullptr);
}
// file in/out
void setIO(string str = "") {
  fastIO();
 
  if (str != "") {
    freopen((str + ".in").c_str(), "r", stdin);
    freopen((str + ".out").c_str(), "w", stdout);
  } else if(str == "input") {
    freopen("input.txt", "r", stdin);
    freopen("output.txt", "w", stdout);
  }
}
 
// Indexed Set
template <class T> using Tree = tree<T, null_type, less<T>, rb_tree_tag, tree_order_statistics_node_update>;
 
const long long inf = -1e16;


long long solve(int N, int K, int *A, int *B) {
  vector<long long> a(2 * N), b(2 * N);
  int n = N, k = K;
 
  long long ans = 0;
  for(int i = 0; i < N; i++) {
    a[i] = A[i];
    b[i] = B[i];
    ans += a[i] - b[i];
  }

  ans = max(ans, 0ll);
 
  if(k == n) {
    return ans;
  }

  for(int t = 0; t <= 1; t++) {
    vector<vector<long long>> dp(n, vector<long long> (k + 1, inf));
    if(t) {
      dp[n - 1][0] = 0;
      dp[n - 1][1] = -b[n - 1];
      for(int i = 2; i <= k; i++) {
        dp[n - 1][i] = dp[n - 1][i - 1] - b[i - 2];
        if(i == k) {
          dp[n - 1][i] += a[n - 1];
        }
      }
    } else {
      for(int i = 0; i <= k; i++) {
        dp[n - 1][i] = 0;
      }
      dp[n - 1][k] = a[n - 1] - b[n - 1];
    }

    for(int i = n - 2; i >= 0; i--) {
      for(int j = 0; j <= k; j++) {
        dp[i][0] = max(dp[i][0], dp[i + 1][j]);
      }

      for(int j = 0; j < k; j++) {
        dp[i][j + 1] = dp[i + 1][j] - b[i];
        if(j + 1 == k) {
          dp[i][j + 1] += a[i];
        }
      }
      dp[i][k] = max(dp[i][k], dp[i + 1][k] - b[i] + a[i]);
    }
    
    if(t) {
      for(int i = 0; i < n; i++) {
        for(int j = 0; j <= k; j++) {
          ans = max(ans, dp[i][j]);
        }
      }
    } else {
      ans= max({ans, dp[0][k], dp[0][k - 1]});
    }
  }


  return ans;
}

Compilation message (stderr)

homecoming.cpp: In function 'void setIO(std::string)':
homecoming.cpp:90:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   90 |     freopen((str + ".in").c_str(), "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
homecoming.cpp:91:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   91 |     freopen((str + ".out").c_str(), "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
homecoming.cpp:93:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   93 |     freopen("input.txt", "r", stdin);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~
homecoming.cpp:94:12: warning: ignoring return value of 'FILE* freopen(const char*, const char*, FILE*)' declared with attribute 'warn_unused_result' [-Wunused-result]
   94 |     freopen("output.txt", "w", stdout);
      |     ~~~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~

• Subtask 1: 0 / 13
• Subtask 2: 0 / 18
• Subtask 3: 0 / 31
• Subtask 4: 0 / 38