#include <cstdio>
#include <algorithm>
#include <vector>
#include <queue>
const int MN = 3e4 + 10;
int N, M, st, end;
std::vector<int> a[MN];
struct state {public: int b, p, d, j;};
std::queue<state> q;
bool u[MN];
int main(void)
{
scanf("%d%d", &N, &M);
for(int i=0,b,p;i<M;++i)
{
scanf("%d%d", &b, &p);
if(i == 0) st = b;
if(i==1) end = b;
else a[b].push_back(p);
}
if(st == end)
return printf("0\n"), 0;
for(int i=0;i<N;++i)
std::sort(a[i].begin(), a[i].end()), a[i].resize(std::distance(a[i].begin(), std::unique(a[i].begin(), a[i].end())));
for(int x : a[st])
{
if(st >= x) q.push({st-x, x, 1, -1});
if(st+x<N) q.push({st+x, x, 1, 1});
}
u[st] = 1;
for(;!q.empty();q.pop())
{
state n = q.front();
if(n.b == end)
return printf("%d\n", n.d), 0;
if(!u[n.b])
{
u[n.b] = 1;
for(int x : a[n.b])
{
if(x == n.p) continue;
if(n.b >= x) q.push({n.b-x, x, n.d+1, -1});
if(n.b+x<N) q.push({n.b+x, x, n.d+1, 1});
}
}
else
{
std::vector<int>::iterator it = std::lower_bound(a[n.b].begin(), a[n.b].end(), n.p);
if(it != a[n.b].end() && *it == n.p) continue;
}
int nx = n.b + n.p*n.j;
if(0 <= nx && nx < N)
q.push({nx, n.p, n.d+1, n.j});
}
printf("-1\n");
return 0;
}
Compilation message
skyscraper.cpp: In function 'int main()':
skyscraper.cpp:15:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &N, &M);
~~~~~^~~~~~~~~~~~~~~~
skyscraper.cpp:18:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
scanf("%d%d", &b, &p);
~~~~~^~~~~~~~~~~~~~~~
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 2 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 3 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 4 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 5 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 6 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 7 |
Correct |
5 ms |
1024 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 2 |
Correct |
5 ms |
1056 KB |
Output is correct |
| 3 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 4 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 5 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 6 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 7 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 8 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 9 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 10 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 11 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 12 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 13 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 14 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 15 |
Correct |
5 ms |
1024 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 2 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 3 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 4 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 5 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 6 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 7 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 8 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 9 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 10 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 11 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 12 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 13 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 14 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 15 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 16 |
Correct |
5 ms |
1056 KB |
Output is correct |
| 17 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 18 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 19 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 20 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 21 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 22 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 23 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 24 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 25 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 26 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 27 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 28 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 29 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 30 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 31 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 32 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 33 |
Correct |
7 ms |
1024 KB |
Output is correct |
| 34 |
Correct |
6 ms |
1024 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 2 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 3 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 4 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 5 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 6 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 7 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 8 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 9 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 10 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 11 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 12 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 13 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 14 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 15 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 16 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 17 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 18 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 19 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 20 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 21 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 22 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 23 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 24 |
Correct |
7 ms |
1024 KB |
Output is correct |
| 25 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 26 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 27 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 28 |
Correct |
6 ms |
1152 KB |
Output is correct |
| 29 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 30 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 31 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 32 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 33 |
Correct |
7 ms |
1024 KB |
Output is correct |
| 34 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 35 |
Correct |
13 ms |
1536 KB |
Output is correct |
| 36 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 37 |
Correct |
11 ms |
1536 KB |
Output is correct |
| 38 |
Correct |
14 ms |
1408 KB |
Output is correct |
| 39 |
Correct |
14 ms |
1280 KB |
Output is correct |
| 40 |
Correct |
13 ms |
1280 KB |
Output is correct |
| 41 |
Correct |
14 ms |
1408 KB |
Output is correct |
| 42 |
Correct |
10 ms |
1280 KB |
Output is correct |
| 43 |
Correct |
11 ms |
1280 KB |
Output is correct |
| 44 |
Correct |
11 ms |
1280 KB |
Output is correct |
| 45 |
Correct |
19 ms |
1664 KB |
Output is correct |
| 46 |
Correct |
19 ms |
1664 KB |
Output is correct |
| # |
Verdict |
Execution time |
Memory |
Grader output |
| 1 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 2 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 3 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 4 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 5 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 6 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 7 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 8 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 9 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 10 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 11 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 12 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 13 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 14 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 15 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 16 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 17 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 18 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 19 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 20 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 21 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 22 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 23 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 24 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 25 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 26 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 27 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 28 |
Correct |
6 ms |
1152 KB |
Output is correct |
| 29 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 30 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 31 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 32 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 33 |
Correct |
7 ms |
1024 KB |
Output is correct |
| 34 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 35 |
Correct |
13 ms |
1408 KB |
Output is correct |
| 36 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 37 |
Correct |
10 ms |
1536 KB |
Output is correct |
| 38 |
Correct |
14 ms |
1408 KB |
Output is correct |
| 39 |
Correct |
17 ms |
1408 KB |
Output is correct |
| 40 |
Correct |
14 ms |
1280 KB |
Output is correct |
| 41 |
Correct |
14 ms |
1408 KB |
Output is correct |
| 42 |
Correct |
13 ms |
1280 KB |
Output is correct |
| 43 |
Correct |
11 ms |
1280 KB |
Output is correct |
| 44 |
Correct |
11 ms |
1280 KB |
Output is correct |
| 45 |
Correct |
19 ms |
1664 KB |
Output is correct |
| 46 |
Correct |
16 ms |
1664 KB |
Output is correct |
| 47 |
Correct |
13 ms |
1536 KB |
Output is correct |
| 48 |
Correct |
14 ms |
1408 KB |
Output is correct |
| 49 |
Correct |
13 ms |
1408 KB |
Output is correct |
| 50 |
Correct |
10 ms |
1408 KB |
Output is correct |
| 51 |
Correct |
18 ms |
1792 KB |
Output is correct |
| 52 |
Correct |
18 ms |
1792 KB |
Output is correct |
| 53 |
Correct |
16 ms |
1664 KB |
Output is correct |
| 54 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 55 |
Correct |
5 ms |
1024 KB |
Output is correct |
| 56 |
Correct |
15 ms |
1920 KB |
Output is correct |
| 57 |
Correct |
6 ms |
1024 KB |
Output is correct |
| 58 |
Correct |
11 ms |
1280 KB |
Output is correct |
| 59 |
Correct |
12 ms |
1536 KB |
Output is correct |
| 60 |
Correct |
12 ms |
1536 KB |
Output is correct |
| 61 |
Correct |
12 ms |
1536 KB |
Output is correct |
| 62 |
Correct |
29 ms |
2304 KB |
Output is correct |
| 63 |
Correct |
43 ms |
1792 KB |
Output is correct |
| 64 |
Correct |
49 ms |
1784 KB |
Output is correct |
| 65 |
Correct |
64 ms |
1912 KB |
Output is correct |
| 66 |
Correct |
101 ms |
1920 KB |
Output is correct |
| 67 |
Correct |
61 ms |
1920 KB |
Output is correct |
