ID | Problem | Submitter | Result | Time | Memory | Language | File size | Submit time | Judge time |
---|---|---|---|---|---|---|---|---|---|
#214235 | #2763. 幻想乡的拜访 | nullptr_qwq | 100 | 2009ms | 65736kb | C++11 | 5.5kb | 2024-11-16 18:55:26 | 2024-11-16 23:10:58 |
answer
// 私は猫です
#include<bits/stdc++.h>
#define ull unsigned long long
#define ll long long
#define pb push_back
#define mkp make_pair
#define fi first
#define se second
#define inf 1000000000
#define infll 1000000000000000000ll
#define pii pair<int,int>
#define rep(i,a,b,c) for(int i=(a);i<=(b);i+=(c))
#define per(i,a,b,c) for(int i=(a);i>=(b);i-=(c))
#define F(i,a,b) for(int i=a,i##end=b;i<=i##end;i++)
#define dF(i,a,b) for(int i=a,i##end=b;i>=i##end;i--)
#define cmh(sjy) while(sjy--)
#define lowbit(x) (x&(-x))
#define HH printf("\n")
#define eb emplace_back
#define poly vector<int>
#define SZ(x) ((int)x.size())
using namespace std;
ll read(){
ll x=0,f=1;char c=getchar();
while(c<'0'||c>'9'){if(c=='-') f=-1;c=getchar();}
while(c>='0'&&c<='9') x=(x<<3)+(x<<1)+(c^48),c=getchar();
return x*f;
}
namespace Fastio{struct Reader{template<typename T>Reader&operator>>(T&x){x=0;short f=1;char c=getchar();while(c<'0'||c>'9'){if(c=='-')f*=-1;c=getchar();}while(c>='0'&&c<='9')x=(x<<3)+(x<<1)+(c^48),c=getchar();x*=f;return*this;}Reader&operator>>(double&x){x=0;double t=0;short f=1,s=0;char c=getchar();while((c<'0'||c>'9')&&c!='.'){if(c=='-')f*=-1;c=getchar();}while(c>='0'&&c<='9'&&c!='.')x=x*10+(c^48),c=getchar();if(c=='.')c=getchar();else{x*=f;return*this;}while(c>='0'&&c<='9')t=t*10+(c^48),s++,c=getchar();while(s--)t/=10.0;x=(x+t)*f;return*this;}Reader&operator>>(long double&x){x=0;long double t=0;short f=1,s=0;char c=getchar();while((c<'0'||c>'9')&&c!='.'){if(c=='-')f*=-1;c=getchar();}while(c>='0'&&c<='9'&&c!='.')x=x*10+(c^48),c=getchar();if(c=='.')c=getchar();else{x*=f;return*this;}while(c>='0'&&c<='9')t=t*10+(c^48),s++,c=getchar();while(s--)t/=10.0;x=(x+t)*f;return*this;}Reader&operator>>(__float128&x){x=0;__float128 t=0;short f=1,s=0;char c=getchar();while((c<'0'||c>'9')&&c!='.'){if(c=='-')f*=-1;c=getchar();}while(c>='0'&&c<='9'&&c!='.')x=x*10+(c^48),c=getchar();if(c=='.')c=getchar();else{x*=f;return*this;}while(c>='0'&&c<='9')t=t*10+(c^48),s++,c=getchar();while(s--)t/=10.0;x=(x+t)*f;return*this;}Reader&operator>>(char&c){c=getchar();while(c==' '||c=='\n'||c=='\r')c=getchar();return*this;}Reader&operator>>(char*str){int len=0;char c=getchar();while(c==' '||c=='\n'||c=='\r')c=getchar();while(c!=' '&&c!='\n'&&c!='\r')str[len++]=c,c=getchar();str[len]='\0';return*this;}Reader&operator>>(string&str){str.clear();char c=getchar();while(c==' '||c=='\n'||c=='\r')c=getchar();while(c!=' '&&c!='\n'&&c!='\r')str.push_back(c),c=getchar();return*this;}Reader(){}}cin;const char endl='\n';struct Writer{const int Setprecision=6;typedef int mxdouble;template<typename T>Writer&operator<<(T x){if(x==0){putchar('0');return*this;}if(x<0)putchar('-'),x=-x;static short sta[40];short top=0;while(x>0)sta[++top]=x%10,x/=10;while(top>0)putchar(sta[top]+'0'),top--;return*this;}Writer&operator<<(double x){if(x<0)putchar('-'),x=-x;mxdouble _=x;x-=(double)_;static short sta[40];short top=0;while(_>0)sta[++top]=_%10,_/=10;if(top==0)putchar('0');while(top>0)putchar(sta[top]+'0'),top--;putchar('.');for(int i=0;i<Setprecision;i++)x*=10;_=x;while(_>0)sta[++top]=_%10,_/=10;for(int i=0;i<Setprecision-top;i++)putchar('0');while(top>0)putchar(sta[top]+'0'),top--;return*this;}Writer&operator<<(long double x){if(x<0)putchar('-'),x=-x;mxdouble _=x;x-=(long double)_;static short sta[40];short top=0;while(_>0)sta[++top]=_%10,_/=10;if(top==0)putchar('0');while(top>0)putchar(sta[top]+'0'),top--;putchar('.');for(int i=0;i<Setprecision;i++)x*=10;_=x;while(_>0)sta[++top]=_%10,_/=10;for(int i=0;i<Setprecision-top;i++)putchar('0');while(top>0)putchar(sta[top]+'0'),top--;return*this;}Writer&operator<<(__float128 x){if(x<0)putchar('-'),x=-x;mxdouble _=x;x-=(__float128)_;static short sta[40];short top=0;while(_>0)sta[++top]=_%10,_/=10;if(top==0)putchar('0');while(top>0)putchar(sta[top]+'0'),top--;putchar('.');for(int i=0;i<Setprecision;i++)x*=10;_=x;while(_>0)sta[++top]=_%10,_/=10;for(int i=0;i<Setprecision-top;i++)putchar('0');while(top>0)putchar(sta[top]+'0'),top--;return*this;}Writer&operator<<(char c){putchar(c);return*this;}Writer&operator<<(char*str){int cur=0;while(str[cur])putchar(str[cur++]);return*this;}Writer&operator<<(const char*str){int cur=0;while(str[cur])putchar(str[cur++]);return*this;}Writer&operator<<(string str){int st=0,ed=str.size();while(st<ed)putchar(str[st++]);return*this;}Writer(){}}cout;}using namespace Fastio;
#define cin Fastio::cin
#define cout Fastio::cout
#define endl Fastio::endl
template<typename T>inline void chkmax(T &x,const T &y){ x=std::max(x,y); }
template<typename T>inline void chkmin(T &x,const T &y){ x=std::min(x,y); }
const int mod=1e9+7,maxn=1000005;
inline int qpow(int x,ll y){
int rt=1;
for(;y;y>>=1,x=1ll*x*x%mod) if(y&1) rt=1ll*rt*x%mod;
return rt;
}
inline void inc(int &x,const int y){ x=(x+y>=mod)?(x+y-mod):(x+y); }
inline void dec(int &x,const int y){ x=(x>=y)?(x-y):(x+mod-y); }
inline void mul(int &x,const int y){ x=1ll*x*y%mod; }
inline int add(const int x,const int y){ return (x+y>=mod)?(x+y-mod):(x+y); }
inline int sub(const int x,const int y){ return (x>=y)?(x-y):(x+mod-y); }
inline int prod(const int x,const int y){ return 1ll*x*y%mod; }
int siz[maxn],sum,n,ans;
vector<int>g[maxn];
void dfs(int u,int fa=0){
siz[u]=u;
for(auto v:g[u])if(v^fa)dfs(v,u),inc(siz[u],siz[v]);
if(fa)inc(ans,1ll*siz[u]*sub(sum,siz[u])%mod);
}
void solve(){
cin>>n;
F(i,1,n)inc(sum,i);
F(i,1,n-1){int u,v; cin>>u>>v;g[u].push_back(v),g[v].push_back(u);}
dfs(1),cout<<ans;
}
signed main(){
// ios::sync_with_stdio(0),cin.tie(0),cout.tie(0);
int zsy=1;
F(____,1,zsy)solve();
}
Details
小提示:点击横条可展开更详细的信息
Test #1:
score: 10
Accepted
time: 8ms
memory: 24616kb
input:
200 20 160 90 160 5 90 78 90 186 90 149 90 104 78 136 160 106 78 100 106 168 90 30 5 85 136 28 149 1...
output:
104425891
result:
ok single line: '104425891'
Test #2:
score: 10
Accepted
time: 4ms
memory: 24612kb
input:
200 49 91 20 91 147 91 131 20 36 131 9 131 51 147 173 51 32 36 169 51 180 51 2 91 133 2 72 20 14 169...
output:
145567217
result:
ok single line: '145567217'
Test #3:
score: 10
Accepted
time: 9ms
memory: 24616kb
input:
200 44 72 187 72 115 72 124 115 80 124 34 72 22 115 162 34 123 44 93 22 135 80 5 124 112 72 76 187 3...
output:
226420652
result:
ok single line: '226420652'
Test #4:
score: 10
Accepted
time: 3ms
memory: 24728kb
input:
3000 940 1649 220 1649 1438 1649 2264 1649 1467 940 1825 220 1646 940 571 220 1419 220 2509 1438 264...
output:
781596579
result:
ok single line: '781596579'
Test #5:
score: 10
Accepted
time: 3ms
memory: 24728kb
input:
3000 2156 216 2422 2156 2801 216 2504 2156 2701 2156 2582 2801 1558 2156 864 2582 737 864 2919 1558 ...
output:
236427659
result:
ok single line: '236427659'
Test #6:
score: 10
Accepted
time: 9ms
memory: 24724kb
input:
3000 2966 2885 2657 2885 2613 2966 1686 2613 2803 2885 191 2657 2824 2657 675 2657 2693 191 2798 191...
output:
688220644
result:
ok single line: '688220644'
Test #7:
score: 10
Accepted
time: 467ms
memory: 65712kb
input:
1000000 984750 990109 970095 984750 996126 970095 998081 990109 987074 970095 962711 970095 916630 9...
output:
192557796
result:
ok single line: '192557796'
Test #8:
score: 10
Accepted
time: 651ms
memory: 65564kb
input:
1000000 947305 936749 948062 947305 970449 947305 988744 948062 998703 988744 986194 947305 997762 9...
output:
160385007
result:
ok single line: '160385007'
Test #9:
score: 10
Accepted
time: 461ms
memory: 65736kb
input:
1000000 952012 962256 982471 962256 955412 952012 953636 962256 991390 952012 998704 953636 999294 9...
output:
308556344
result:
ok single line: '308556344'
Test #10:
score: 10
Accepted
time: 394ms
memory: 65692kb
input:
1000000 900864 972452 986047 900864 953966 972452 977801 986047 997024 972452 954755 953966 999240 9...
output:
201471911
result:
ok single line: '201471911'