oj.uz

Submission #24326

# Submission time Handle Problem Language Result Execution time Memory
24326 2017-06-05T12:33:04 Z jiaqiyang Railway Trip (JOI17_railway_trip) C++14
100 / 100
 396 ms 17524 KB 
#include <cstdio>
#include <tuple>
#include <algorithm>

const int N = 100000 + 10;

int n, a[N];

std::pair<int, int> f[20][N];

int init() {
  int q;
  scanf("%d%*d%d", &n, &q);
  for (int i = 1; i <= n; ++i) scanf("%d", &a[i]);
  static int stk[N];
  f[0][n].second = n;
  for (int i = 1, top = 0; i <= n; ++i) {
    for (; top && a[i] >= a[stk[top]]; --top) f[0][stk[top]].second = i;
    stk[++top] = i;
  }
  f[0][1].first = 1;
  for (int i = n, top = 0; i > 0; --i) {
    for (; top && a[i] >= a[stk[top]]; --top) f[0][stk[top]].first = i;
    stk[++top] = i;
  }
  for (int i = 1; i < 20; ++i) {
    for (int j = 1; j <= n; ++j) {
      int x, y;
      std::tie(x, y) = f[i - 1][j];
      f[i][j] = {std::min(f[i - 1][x].first, f[i - 1][y].first), std::max(f[i - 1][x].second, f[i - 1][y].second)};
    }
  }
  return q;
}

int main() {
  for (int q = init(); q--;) {
    int l, r;
    scanf("%d%d", &l, &r);
    if (l > r) std::swap(l, r);
    int ans = 0, x = l, y = l;
    for (int i = 19; i >= 0; --i) {
      if (std::max(f[i][x].second, f[i][y].second) >= r) continue;
      ans += 1 << i;
      std::tie(x, y) = std::make_tuple(std::min(f[i][x].first, f[i][y].first), std::max(f[i][x].second, f[i][y].second));
    }
    l = y;
    x = y = r;
    for (int i = 19; i >= 0; --i) {
      if (std::min(f[i][x].first, f[i][y].first) <= l) continue;
      ans += 1 << i;
      std::tie(x, y) = std::make_tuple(std::min(f[i][x].first, f[i][y].first), std::max(f[i][x].second, f[i][y].second));
    }
    printf("%d\n", ans);
  }
  return 0;
}

Compilation message

railway_trip.cpp: In function 'int init()':
railway_trip.cpp:13:27: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%*d%d", &n, &q);
                           ^
railway_trip.cpp:14:50: 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]);
                                                  ^
railway_trip.cpp: In function 'int main()':
railway_trip.cpp:39:26: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d%d", &l, &r);
                          ^

Subtask #1
5.0 / 5.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 17524 KB Output is correct
2 Correct 0 ms 17524 KB Output is correct
3 Correct 0 ms 17524 KB Output is correct
4 Correct 0 ms 17524 KB Output is correct
5 Correct 0 ms 17524 KB Output is correct
6 Correct 0 ms 17524 KB Output is correct
7 Correct 0 ms 17524 KB Output is correct
8 Correct 0 ms 17524 KB Output is correct
9 Correct 0 ms 17524 KB Output is correct

Subtask #2
15.0 / 15.0

# Verdict Execution time Memory Grader output
1 Correct 0 ms 17524 KB Output is correct
2 Correct 19 ms 17524 KB Output is correct
3 Correct 23 ms 17524 KB Output is correct
4 Correct 19 ms 17524 KB Output is correct
5 Correct 23 ms 17524 KB Output is correct
6 Correct 23 ms 17524 KB Output is correct
7 Correct 26 ms 17524 KB Output is correct
8 Correct 9 ms 17524 KB Output is correct
9 Correct 16 ms 17524 KB Output is correct
10 Correct 16 ms 17524 KB Output is correct
11 Correct 26 ms 17524 KB Output is correct
12 Correct 26 ms 17524 KB Output is correct
13 Correct 23 ms 17524 KB Output is correct
14 Correct 36 ms 17524 KB Output is correct
15 Correct 26 ms 17524 KB Output is correct
16 Correct 26 ms 17524 KB Output is correct
17 Correct 26 ms 17524 KB Output is correct
18 Correct 29 ms 17524 KB Output is correct
19 Correct 29 ms 17524 KB Output is correct

Subtask #3
25.0 / 25.0

# Verdict Execution time Memory Grader output
1 Correct 316 ms 17524 KB Output is correct
2 Correct 299 ms 17524 KB Output is correct
3 Correct 279 ms 17524 KB Output is correct
4 Correct 236 ms 17524 KB Output is correct
5 Correct 226 ms 17524 KB Output is correct
6 Correct 269 ms 17524 KB Output is correct
7 Correct 253 ms 17524 KB Output is correct
8 Correct 296 ms 17524 KB Output is correct
9 Correct 396 ms 17524 KB Output is correct
10 Correct 343 ms 17524 KB Output is correct
11 Correct 363 ms 17524 KB Output is correct
12 Correct 276 ms 17524 KB Output is correct
13 Correct 349 ms 17524 KB Output is correct
14 Correct 276 ms 17524 KB Output is correct
15 Correct 159 ms 17524 KB Output is correct
16 Correct 219 ms 17524 KB Output is correct

Subtask #4
55.0 / 55.0

# Verdict Execution time Memory Grader output
1 Correct 176 ms 17524 KB Output is correct
2 Correct 199 ms 17524 KB Output is correct
3 Correct 159 ms 17524 KB Output is correct
4 Correct 149 ms 17524 KB Output is correct
5 Correct 303 ms 17524 KB Output is correct
6 Correct 259 ms 17524 KB Output is correct
7 Correct 303 ms 17524 KB Output is correct
8 Correct 303 ms 17524 KB Output is correct
9 Correct 299 ms 17524 KB Output is correct
10 Correct 269 ms 17524 KB Output is correct
11 Correct 283 ms 17524 KB Output is correct
12 Correct 266 ms 17524 KB Output is correct
13 Correct 263 ms 17524 KB Output is correct
14 Correct 179 ms 17524 KB Output is correct
15 Correct 206 ms 17524 KB Output is correct
16 Correct 293 ms 17524 KB Output is correct
17 Correct 223 ms 17524 KB Output is correct
18 Correct 276 ms 17524 KB Output is correct
19 Correct 243 ms 17524 KB Output is correct
20 Correct 213 ms 17524 KB Output is correct
21 Correct 143 ms 17524 KB Output is correct
22 Correct 203 ms 17524 KB Output is correct
23 Correct 209 ms 17524 KB Output is correct