#include <bits/stdc++.h>
using namespace std;
typedef long long ll;
const int mod=1e9+7;
int n,m;
int lastmare[500005],lastmic[500005];
int dp[3][28][500005]; /// 0 -> egal, 1 -> mai mic, 2 -> mai mare
int spref[3][28][500005],ssuf[3][28][500005];
int rmq[2][21][500005]; /// 0 -> lastmic, 1 -> lastmare
int loga[500005];
int getmax(int tip,int l,int r)
{
int lg=loga[r-l+1];
return max(rmq[tip][lg][l],rmq[tip][lg][r-(1<<lg)+1]);
}
int main()
{
ios_base::sync_with_stdio(false);
cin.tie(0);
cin>>n>>m;
for(int i=1;i<=m;i++)
{
int a,b;
cin>>a>>b;
if(a<b)
lastmic[a]=max(lastmic[a],b);
if(a>b)
lastmare[b]=max(lastmare[b],a);
}
for(int i=1;i<=n;i++)
{
for(int bit=0;bit<=20;bit++)
if((1<<bit)<=i)
loga[i]=bit;
rmq[0][0][i]=lastmic[i];
rmq[1][0][i]=lastmare[i];
}
for(int tip=0;tip<=1;tip++)
for(int j=1;j<=20;j++)
for(int i=1;i<=n;i++)
{
rmq[tip][j][i]=rmq[tip][j-1][i];
int poz=i+(1<<(j-1));
if(poz<=n)
rmq[tip][j][i]=max(rmq[tip][j][i],rmq[tip][j-1][poz]);
}
for(int i=1;i<=26;i++)
dp[2][i][1]=1;
for(int tip=1;tip<=2;tip++)
{
int suma=0;
for(int c=1;c<=26;c++)
{
suma=(suma+dp[tip][c][1])%mod;
spref[tip][c][1]=(spref[tip][c][0]+suma)%mod;
}
}
for(int tip=1;tip<=2;tip++)
{
int suma=0;
for(int c=26;c>=1;c--)
{
suma=(suma+dp[tip][c][1])%mod;
ssuf[tip][c][1]=(ssuf[tip][c][0]+suma)%mod;
}
}
for(int i=2;i<=n;i++)
{
int pmare=i,pmic=i;
/// mai mare
int st=1;
int dr=i-1;
while(st<=dr)
{
int mij=(st+dr)/2;
if(getmax(0,mij,i-1)<i)
{
pmare=mij;
dr=mij-1;
}
else
st=mij+1;
}
/// mai mic
st=1;
dr=i-1;
while(st<=dr)
{
int mij=(st+dr)/2;
if(getmax(1,mij,i-1)<i)
{
pmic=mij;
dr=mij-1;
}
else
st=mij+1;
}
for(int c=1;c<=26;c++)
{
dp[0][c][i]=(1LL*dp[0][c][i-1]+1LL*dp[1][c][i-1]+1LL*dp[2][c][i-1])%mod;
int x=(spref[1][c-1][i-1]-spref[1][c-1][pmic-1]+mod)%mod;
int y=(spref[2][c-1][i-1]-spref[2][c-1][pmic-1]+mod)%mod;
dp[1][c][i]=(x+y)%mod;
x=(ssuf[1][c+1][i-1]-ssuf[1][c+1][pmare-1]+mod)%mod;
y=(ssuf[2][c+1][i-1]-ssuf[2][c+1][pmare-1]+mod)%mod;
dp[2][c][i]=(x+y)%mod;
}
for(int tip=1;tip<=2;tip++)
{
int suma=0;
for(int c=1;c<=26;c++)
{
suma=(suma+dp[tip][c][i])%mod;
spref[tip][c][i]=(spref[tip][c][i-1]+suma)%mod;
}
}
for(int tip=1;tip<=2;tip++)
{
int suma=0;
for(int c=26;c>=1;c--)
{
suma=(suma+dp[tip][c][i])%mod;
ssuf[tip][c][i]=(ssuf[tip][c][i-1]+suma)%mod;
}
}
}
int ans=0;
for(int c=1;c<=26;c++)
{
ans=(ans+dp[0][c][n])%mod;
ans=(ans+dp[1][c][n])%mod;
ans=(ans+dp[2][c][n])%mod;
}
cout<<ans;
return 0;
}
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
26 ms |
134992 KB |
Output is correct |
2 |
Correct |
16 ms |
134988 KB |
Output is correct |
3 |
Correct |
16 ms |
135000 KB |
Output is correct |
4 |
Correct |
17 ms |
134916 KB |
Output is correct |
5 |
Correct |
16 ms |
134956 KB |
Output is correct |
6 |
Correct |
16 ms |
135004 KB |
Output is correct |
7 |
Correct |
16 ms |
135004 KB |
Output is correct |
8 |
Correct |
16 ms |
135000 KB |
Output is correct |
9 |
Correct |
16 ms |
134980 KB |
Output is correct |
10 |
Correct |
16 ms |
135180 KB |
Output is correct |
11 |
Correct |
17 ms |
135004 KB |
Output is correct |
12 |
Correct |
16 ms |
135036 KB |
Output is correct |
13 |
Correct |
16 ms |
135004 KB |
Output is correct |
14 |
Correct |
17 ms |
135004 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
26 ms |
134992 KB |
Output is correct |
2 |
Correct |
16 ms |
134988 KB |
Output is correct |
3 |
Correct |
16 ms |
135000 KB |
Output is correct |
4 |
Correct |
17 ms |
134916 KB |
Output is correct |
5 |
Correct |
16 ms |
134956 KB |
Output is correct |
6 |
Correct |
16 ms |
135004 KB |
Output is correct |
7 |
Correct |
16 ms |
135004 KB |
Output is correct |
8 |
Correct |
16 ms |
135000 KB |
Output is correct |
9 |
Correct |
16 ms |
134980 KB |
Output is correct |
10 |
Correct |
16 ms |
135180 KB |
Output is correct |
11 |
Correct |
17 ms |
135004 KB |
Output is correct |
12 |
Correct |
16 ms |
135036 KB |
Output is correct |
13 |
Correct |
16 ms |
135004 KB |
Output is correct |
14 |
Correct |
17 ms |
135004 KB |
Output is correct |
15 |
Correct |
16 ms |
135004 KB |
Output is correct |
16 |
Correct |
16 ms |
135000 KB |
Output is correct |
17 |
Correct |
17 ms |
135004 KB |
Output is correct |
18 |
Correct |
16 ms |
135260 KB |
Output is correct |
19 |
Correct |
17 ms |
135260 KB |
Output is correct |
20 |
Correct |
18 ms |
135004 KB |
Output is correct |
21 |
Correct |
17 ms |
135096 KB |
Output is correct |
22 |
Correct |
18 ms |
135004 KB |
Output is correct |
23 |
Correct |
16 ms |
135004 KB |
Output is correct |
24 |
Correct |
16 ms |
135032 KB |
Output is correct |
25 |
Correct |
17 ms |
135004 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
18 ms |
135004 KB |
Output is correct |
2 |
Correct |
24 ms |
134992 KB |
Output is correct |
3 |
Correct |
17 ms |
135004 KB |
Output is correct |
4 |
Correct |
16 ms |
135004 KB |
Output is correct |
5 |
Correct |
763 ms |
451148 KB |
Output is correct |
6 |
Correct |
700 ms |
451144 KB |
Output is correct |
7 |
Correct |
705 ms |
457772 KB |
Output is correct |
8 |
Correct |
689 ms |
457556 KB |
Output is correct |
9 |
Correct |
691 ms |
457660 KB |
Output is correct |
10 |
Correct |
43 ms |
149600 KB |
Output is correct |
11 |
Correct |
16 ms |
135004 KB |
Output is correct |
12 |
Correct |
17 ms |
135000 KB |
Output is correct |
13 |
Correct |
746 ms |
457732 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
26 ms |
134992 KB |
Output is correct |
2 |
Correct |
16 ms |
134988 KB |
Output is correct |
3 |
Correct |
16 ms |
135000 KB |
Output is correct |
4 |
Correct |
17 ms |
134916 KB |
Output is correct |
5 |
Correct |
16 ms |
134956 KB |
Output is correct |
6 |
Correct |
16 ms |
135004 KB |
Output is correct |
7 |
Correct |
16 ms |
135004 KB |
Output is correct |
8 |
Correct |
16 ms |
135000 KB |
Output is correct |
9 |
Correct |
16 ms |
134980 KB |
Output is correct |
10 |
Correct |
16 ms |
135180 KB |
Output is correct |
11 |
Correct |
17 ms |
135004 KB |
Output is correct |
12 |
Correct |
16 ms |
135036 KB |
Output is correct |
13 |
Correct |
16 ms |
135004 KB |
Output is correct |
14 |
Correct |
17 ms |
135004 KB |
Output is correct |
15 |
Correct |
16 ms |
135004 KB |
Output is correct |
16 |
Correct |
16 ms |
135000 KB |
Output is correct |
17 |
Correct |
17 ms |
135004 KB |
Output is correct |
18 |
Correct |
16 ms |
135260 KB |
Output is correct |
19 |
Correct |
17 ms |
135260 KB |
Output is correct |
20 |
Correct |
18 ms |
135004 KB |
Output is correct |
21 |
Correct |
17 ms |
135096 KB |
Output is correct |
22 |
Correct |
18 ms |
135004 KB |
Output is correct |
23 |
Correct |
16 ms |
135004 KB |
Output is correct |
24 |
Correct |
16 ms |
135032 KB |
Output is correct |
25 |
Correct |
17 ms |
135004 KB |
Output is correct |
26 |
Correct |
42 ms |
149328 KB |
Output is correct |
27 |
Correct |
47 ms |
149316 KB |
Output is correct |
28 |
Correct |
41 ms |
149328 KB |
Output is correct |
29 |
Correct |
45 ms |
149588 KB |
Output is correct |
30 |
Correct |
47 ms |
149744 KB |
Output is correct |
31 |
Correct |
109 ms |
154664 KB |
Output is correct |
32 |
Correct |
44 ms |
149652 KB |
Output is correct |
33 |
Correct |
43 ms |
149576 KB |
Output is correct |
34 |
Correct |
44 ms |
149792 KB |
Output is correct |
35 |
Correct |
104 ms |
154740 KB |
Output is correct |
36 |
Correct |
42 ms |
149376 KB |
Output is correct |
37 |
Correct |
44 ms |
149600 KB |
Output is correct |
38 |
Correct |
46 ms |
149560 KB |
Output is correct |
39 |
Correct |
42 ms |
149572 KB |
Output is correct |
# |
Verdict |
Execution time |
Memory |
Grader output |
1 |
Correct |
26 ms |
134992 KB |
Output is correct |
2 |
Correct |
16 ms |
134988 KB |
Output is correct |
3 |
Correct |
16 ms |
135000 KB |
Output is correct |
4 |
Correct |
17 ms |
134916 KB |
Output is correct |
5 |
Correct |
16 ms |
134956 KB |
Output is correct |
6 |
Correct |
16 ms |
135004 KB |
Output is correct |
7 |
Correct |
16 ms |
135004 KB |
Output is correct |
8 |
Correct |
16 ms |
135000 KB |
Output is correct |
9 |
Correct |
16 ms |
134980 KB |
Output is correct |
10 |
Correct |
16 ms |
135180 KB |
Output is correct |
11 |
Correct |
17 ms |
135004 KB |
Output is correct |
12 |
Correct |
16 ms |
135036 KB |
Output is correct |
13 |
Correct |
16 ms |
135004 KB |
Output is correct |
14 |
Correct |
17 ms |
135004 KB |
Output is correct |
15 |
Correct |
16 ms |
135004 KB |
Output is correct |
16 |
Correct |
16 ms |
135000 KB |
Output is correct |
17 |
Correct |
17 ms |
135004 KB |
Output is correct |
18 |
Correct |
16 ms |
135260 KB |
Output is correct |
19 |
Correct |
17 ms |
135260 KB |
Output is correct |
20 |
Correct |
18 ms |
135004 KB |
Output is correct |
21 |
Correct |
17 ms |
135096 KB |
Output is correct |
22 |
Correct |
18 ms |
135004 KB |
Output is correct |
23 |
Correct |
16 ms |
135004 KB |
Output is correct |
24 |
Correct |
16 ms |
135032 KB |
Output is correct |
25 |
Correct |
17 ms |
135004 KB |
Output is correct |
26 |
Correct |
18 ms |
135004 KB |
Output is correct |
27 |
Correct |
24 ms |
134992 KB |
Output is correct |
28 |
Correct |
17 ms |
135004 KB |
Output is correct |
29 |
Correct |
16 ms |
135004 KB |
Output is correct |
30 |
Correct |
763 ms |
451148 KB |
Output is correct |
31 |
Correct |
700 ms |
451144 KB |
Output is correct |
32 |
Correct |
705 ms |
457772 KB |
Output is correct |
33 |
Correct |
689 ms |
457556 KB |
Output is correct |
34 |
Correct |
691 ms |
457660 KB |
Output is correct |
35 |
Correct |
43 ms |
149600 KB |
Output is correct |
36 |
Correct |
16 ms |
135004 KB |
Output is correct |
37 |
Correct |
17 ms |
135000 KB |
Output is correct |
38 |
Correct |
746 ms |
457732 KB |
Output is correct |
39 |
Correct |
42 ms |
149328 KB |
Output is correct |
40 |
Correct |
47 ms |
149316 KB |
Output is correct |
41 |
Correct |
41 ms |
149328 KB |
Output is correct |
42 |
Correct |
45 ms |
149588 KB |
Output is correct |
43 |
Correct |
47 ms |
149744 KB |
Output is correct |
44 |
Correct |
109 ms |
154664 KB |
Output is correct |
45 |
Correct |
44 ms |
149652 KB |
Output is correct |
46 |
Correct |
43 ms |
149576 KB |
Output is correct |
47 |
Correct |
44 ms |
149792 KB |
Output is correct |
48 |
Correct |
104 ms |
154740 KB |
Output is correct |
49 |
Correct |
42 ms |
149376 KB |
Output is correct |
50 |
Correct |
44 ms |
149600 KB |
Output is correct |
51 |
Correct |
46 ms |
149560 KB |
Output is correct |
52 |
Correct |
42 ms |
149572 KB |
Output is correct |
53 |
Correct |
692 ms |
453344 KB |
Output is correct |
54 |
Correct |
702 ms |
452536 KB |
Output is correct |
55 |
Correct |
752 ms |
457572 KB |
Output is correct |
56 |
Correct |
779 ms |
457644 KB |
Output is correct |
57 |
Correct |
701 ms |
457640 KB |
Output is correct |
58 |
Correct |
835 ms |
457756 KB |
Output is correct |
59 |
Correct |
764 ms |
457672 KB |
Output is correct |
60 |
Correct |
750 ms |
457720 KB |
Output is correct |
61 |
Correct |
633 ms |
447244 KB |
Output is correct |
62 |
Correct |
711 ms |
456028 KB |
Output is correct |
63 |
Correct |
732 ms |
454272 KB |
Output is correct |
64 |
Correct |
698 ms |
452724 KB |
Output is correct |