Submission #256933

# Submission time Handle Problem Language Result Execution time Memory
256933 2020-08-03T12:09:45 Z Bruteforceman Discharging (NOI20_discharging) C++11
36 / 100
1000 ms 340316 KB
#include <bits/stdc++.h>
using namespace std;
const int maxn = 1e6 + 10;
const long long inf = 1e16;
long long dp[maxn];
int a[maxn];
int n;

struct hull {
  vector <long long> M, C;
  int pt;
  hull() {
    pt = 0;
  }
  bool bad(int i, int j, int k) {
    return (C[k] - C[j]) * (M[i] - M[k]) <= (C[k] - C[i]) * (M[j] - M[k]);
  }
  void add(long long m, long long c) {
    M.push_back(m);
    C.push_back(c);
    while(M.size() >= 3 && bad(M.size() - 3, M.size() - 2, M.size() - 1)) {
      M.erase(M.end() - 2);
      C.erase(C.end() - 2);
    }
    pt = min(pt, int(M.size()) - 1);
  }
  long long eval(long long x) {
    if(M.size() == 0) return inf;
    while(pt + 1 < M.size() && 
        M[pt] * x + C[pt] >= M[pt + 1] * x + C[pt + 1]) {
      ++pt;
    }
    return M[pt] * x + C[pt];
  }
} t[maxn * 4];
void update(int x, int c = 1, int b = 0, int e = n) {
  t[c].add(n - x, dp[x]);
  if(b == e) {
    return ;
  }
  int m = (b + e) >> 1;
  int l = c << 1;
  int r = l + 1;
  if(x <= m) update(x, l, b, m);
  else update(x, r, m + 1, e);
}
long long query(int x, int y, int val, int c = 1, int b = 0, int e = n) {
  if(x <= b && e <= y) {
    return t[c].eval(val);
  }
  if(y < b || e < x) return inf;
  int m = (b + e) >> 1;
  int l = c << 1;
  int r = l + 1;
  return min(query(x, y, val, l, b, m), query(x, y, val, r, m + 1, e));
}
int main() {
  scanf("%d", &n);
  for(int i = 1; i <= n; i++) scanf("%d", &a[i]);
  vector <int> v ({0});
  a[0] = INT_MAX;
  update(0);
  dp[0] = inf;
  for(int i = 1; i <= n; i++) {
    while(a[v.back()] <= a[i]) {
      v.pop_back();
    }
    dp[i] = min(dp[v.back()], query(v.back(), i - 1, a[i]));
    update(i);
    v.push_back(i);
  }
  printf("%lld\n", dp[n]);
  return 0;
}

Compilation message

Discharging.cpp: In member function 'long long int hull::eval(long long int)':
Discharging.cpp:29:18: warning: comparison between signed and unsigned integer expressions [-Wsign-compare]
     while(pt + 1 < M.size() && 
           ~~~~~~~^~~~~~~~~~
Discharging.cpp: In function 'int main()':
Discharging.cpp:58:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d", &n);
   ~~~~~^~~~~~~~~~
Discharging.cpp:59:36: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   for(int i = 1; i <= n; i++) scanf("%d", &a[i]);
                               ~~~~~^~~~~~~~~~~~~
# Verdict Execution time Memory Grader output
1 Correct 138 ms 219512 KB Output is correct
2 Correct 140 ms 219512 KB Output is correct
3 Correct 141 ms 219512 KB Output is correct
4 Correct 143 ms 219640 KB Output is correct
5 Correct 138 ms 219512 KB Output is correct
6 Correct 143 ms 219512 KB Output is correct
7 Correct 128 ms 219640 KB Output is correct
8 Correct 138 ms 219512 KB Output is correct
9 Correct 138 ms 219512 KB Output is correct
10 Correct 134 ms 219496 KB Output is correct
11 Correct 122 ms 219512 KB Output is correct
12 Correct 123 ms 219512 KB Output is correct
13 Correct 118 ms 219512 KB Output is correct
14 Correct 124 ms 219512 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 128 ms 219756 KB Output is correct
2 Correct 129 ms 219768 KB Output is correct
3 Correct 124 ms 219768 KB Output is correct
4 Correct 130 ms 219768 KB Output is correct
5 Correct 143 ms 219896 KB Output is correct
6 Correct 147 ms 219768 KB Output is correct
7 Correct 139 ms 219896 KB Output is correct
8 Correct 130 ms 219680 KB Output is correct
9 Correct 125 ms 219768 KB Output is correct
10 Correct 132 ms 219768 KB Output is correct
11 Correct 146 ms 219768 KB Output is correct
12 Correct 125 ms 219768 KB Output is correct
13 Correct 123 ms 219768 KB Output is correct
14 Correct 130 ms 219952 KB Output is correct
15 Correct 126 ms 219820 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 128 ms 219756 KB Output is correct
2 Correct 129 ms 219768 KB Output is correct
3 Correct 124 ms 219768 KB Output is correct
4 Correct 130 ms 219768 KB Output is correct
5 Correct 143 ms 219896 KB Output is correct
6 Correct 147 ms 219768 KB Output is correct
7 Correct 139 ms 219896 KB Output is correct
8 Correct 130 ms 219680 KB Output is correct
9 Correct 125 ms 219768 KB Output is correct
10 Correct 132 ms 219768 KB Output is correct
11 Correct 146 ms 219768 KB Output is correct
12 Correct 125 ms 219768 KB Output is correct
13 Correct 123 ms 219768 KB Output is correct
14 Correct 130 ms 219952 KB Output is correct
15 Correct 126 ms 219820 KB Output is correct
16 Execution timed out 1116 ms 335224 KB Time limit exceeded
17 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Execution timed out 1110 ms 340316 KB Time limit exceeded
2 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 138 ms 219512 KB Output is correct
2 Correct 140 ms 219512 KB Output is correct
3 Correct 141 ms 219512 KB Output is correct
4 Correct 143 ms 219640 KB Output is correct
5 Correct 138 ms 219512 KB Output is correct
6 Correct 143 ms 219512 KB Output is correct
7 Correct 128 ms 219640 KB Output is correct
8 Correct 138 ms 219512 KB Output is correct
9 Correct 138 ms 219512 KB Output is correct
10 Correct 134 ms 219496 KB Output is correct
11 Correct 122 ms 219512 KB Output is correct
12 Correct 123 ms 219512 KB Output is correct
13 Correct 118 ms 219512 KB Output is correct
14 Correct 124 ms 219512 KB Output is correct
15 Correct 128 ms 219756 KB Output is correct
16 Correct 129 ms 219768 KB Output is correct
17 Correct 124 ms 219768 KB Output is correct
18 Correct 130 ms 219768 KB Output is correct
19 Correct 143 ms 219896 KB Output is correct
20 Correct 147 ms 219768 KB Output is correct
21 Correct 139 ms 219896 KB Output is correct
22 Correct 130 ms 219680 KB Output is correct
23 Correct 125 ms 219768 KB Output is correct
24 Correct 132 ms 219768 KB Output is correct
25 Correct 146 ms 219768 KB Output is correct
26 Correct 125 ms 219768 KB Output is correct
27 Correct 123 ms 219768 KB Output is correct
28 Correct 130 ms 219952 KB Output is correct
29 Correct 126 ms 219820 KB Output is correct
30 Correct 131 ms 219788 KB Output is correct
31 Correct 121 ms 219768 KB Output is correct
32 Correct 131 ms 219768 KB Output is correct
33 Correct 139 ms 219768 KB Output is correct
34 Correct 142 ms 219768 KB Output is correct
35 Correct 123 ms 219768 KB Output is correct
36 Correct 123 ms 219768 KB Output is correct
37 Correct 123 ms 219768 KB Output is correct
38 Correct 124 ms 219916 KB Output is correct
39 Correct 131 ms 220024 KB Output is correct
40 Correct 120 ms 219768 KB Output is correct
41 Correct 133 ms 219832 KB Output is correct
42 Correct 123 ms 219768 KB Output is correct
43 Correct 119 ms 219768 KB Output is correct
44 Correct 129 ms 219768 KB Output is correct
45 Correct 121 ms 219704 KB Output is correct
46 Correct 129 ms 219768 KB Output is correct
47 Correct 135 ms 219696 KB Output is correct
48 Correct 125 ms 219768 KB Output is correct
49 Correct 128 ms 219768 KB Output is correct
50 Correct 118 ms 219768 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 138 ms 219512 KB Output is correct
2 Correct 140 ms 219512 KB Output is correct
3 Correct 141 ms 219512 KB Output is correct
4 Correct 143 ms 219640 KB Output is correct
5 Correct 138 ms 219512 KB Output is correct
6 Correct 143 ms 219512 KB Output is correct
7 Correct 128 ms 219640 KB Output is correct
8 Correct 138 ms 219512 KB Output is correct
9 Correct 138 ms 219512 KB Output is correct
10 Correct 134 ms 219496 KB Output is correct
11 Correct 122 ms 219512 KB Output is correct
12 Correct 123 ms 219512 KB Output is correct
13 Correct 118 ms 219512 KB Output is correct
14 Correct 124 ms 219512 KB Output is correct
15 Correct 128 ms 219756 KB Output is correct
16 Correct 129 ms 219768 KB Output is correct
17 Correct 124 ms 219768 KB Output is correct
18 Correct 130 ms 219768 KB Output is correct
19 Correct 143 ms 219896 KB Output is correct
20 Correct 147 ms 219768 KB Output is correct
21 Correct 139 ms 219896 KB Output is correct
22 Correct 130 ms 219680 KB Output is correct
23 Correct 125 ms 219768 KB Output is correct
24 Correct 132 ms 219768 KB Output is correct
25 Correct 146 ms 219768 KB Output is correct
26 Correct 125 ms 219768 KB Output is correct
27 Correct 123 ms 219768 KB Output is correct
28 Correct 130 ms 219952 KB Output is correct
29 Correct 126 ms 219820 KB Output is correct
30 Execution timed out 1116 ms 335224 KB Time limit exceeded
31 Halted 0 ms 0 KB -