51 lines
1.1 KiB
C++
51 lines
1.1 KiB
C++
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#include<bits/stdc++.h>
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#ifdef ONLINE_JUDGE
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#define dbg(...)
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#else
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#include "debug.h"
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#endif
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using namespace std;
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#define ll long long
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#define endl '\n'
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#define all(x) x.begin(), x.end()
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#define sz(x) (int)(x).size()
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#define yes cout<<"YES"<<endl
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#define no cout<<"NO"<<endl
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#define FAST (ios_base:: sync_with_stdio(false),cin.tie(NULL));
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ll pow(ll x,ll y,ll m=1e9+7){ll ans=1;x%=m;while(y){if(y&1)ans=(ans*x)%m;x=(x*x)%m;y>>=1;}return ans;}
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const int N=3e5+10, M=1e9+7;
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int dp[N];
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int func(int n)
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{
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if(n==0 || n==1)
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return 1;
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if(dp[n]!=-1) return dp[n];
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dp[n]=(func(n-1)+(2ll*(n-1)*func(n-2))%M)%M;
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return dp[n];
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}
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void solve()
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{
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int n,k;
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cin>>n>>k;
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memset(dp,-1,sizeof(dp));
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int used=0;
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for(int i=0; i<k; ++i)
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{
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int r,c;
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cin>>r>>c;
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used += 2-(r==c);
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}
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int m=n-used;
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int ans=func(m);
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cout<<ans<<endl;
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}
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signed main()
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{
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FAST;
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int TC = 1;
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cin >> TC;
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while (TC--) solve();
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}
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