Codeforces Round #629 (Div. 3)
Codeforces Round #629 (Div. 3)
A.Divisibility Problem
#include<bits/stdc++.h> using namespace std; #define me(a,x) memset(a,x,sizeof(a)) #define sc scanf #define pr printf #define IN freopen("in.txt","r",stdin); #define OUT freopen("out.txt","w",stdout); typedef long long ll; typedef unsigned long long ull; const int N=1e6+6; const int mod=1e9+7; template<typename T>int O(const T& s){cout<<s<<endl;return 0;} template<typename T>void db(T *bg,T *ed){while(bg!=ed)cout<<*bg++<<' ';pr("\n");} template<typename T>void db(vector<T>&it){for(auto i:it)cout<<i<<' ';pr("\n");} inline ll mul_64(ll x,ll y,ll c){return (x*y-(ll)((long double)x/c*y)*c+c)%c;} inline ll ksm(ll a,ll b,ll c){ll ans=1;for(;b;b>>=1,a=a*a%c)if(b&1)ans=ans*a%c;return ans;} inline void exgcd(ll a,ll b,ll &x,ll &y){if(!b)x=1,y=0;else exgcd(b,a%b,y,x),y-=(a/b)*x;} int main(){ //IN int _;cin>>_; while(_--){ ll a,b; sc("%lld%lld",&a,&b); if(a%b==0)O(0); else{ ll x=a/b; O((x+1)*b-a); } } }
B.K-th Beautiful String
#include<bits/stdc++.h> using namespace std; #define me(a,x) memset(a,x,sizeof(a)) #define sc scanf #define pr printf #define IN freopen("in.txt","r",stdin); #define OUT freopen("out.txt","w",stdout); typedef long long ll; typedef unsigned long long ull; const int N=1e6+6; const int mod=1e9+7; template<typename T>int O(const T& s){cout<<s<<endl;return 0;} template<typename T>void db(T *bg,T *ed){while(bg!=ed)cout<<*bg++<<' ';pr("\n");} template<typename T>void db(vector<T>&it){for(auto i:it)cout<<i<<' ';pr("\n");} inline ll mul_64(ll x,ll y,ll c){return (x*y-(ll)((long double)x/c*y)*c+c)%c;} inline ll ksm(ll a,ll b,ll c){ll ans=1;for(;b;b>>=1,a=a*a%c)if(b&1)ans=ans*a%c;return ans;} inline void exgcd(ll a,ll b,ll &x,ll &y){if(!b)x=1,y=0;else exgcd(b,a%b,y,x),y-=(a/b)*x;} int main(){ // IN int _;cin>>_; while(_--){ int n,k; sc("%d%d",&n,&k); if(n==2){ O("bb");continue; } int a=n-2; for(;a;){ int b=n-a-1; if(k>b)k-=b,a--; else break; } for(int i=0;i<a;i++)putchar('a');putchar('b'); for(int i=0;i<n-a-1-k;i++)putchar('a');putchar('b'); for(int i=0;i<k-1;i++)putchar('a');putchar(10); } }
C.Ternary XOR
#include<bits/stdc++.h> using namespace std; #define me(a,x) memset(a,x,sizeof(a)) #define sc scanf #define pr printf #define IN freopen("in.txt","r",stdin); #define OUT freopen("out.txt","w",stdout); typedef long long ll; typedef unsigned long long ull; const int N=1e6+6; const int mod=1e9+7; template<typename T>int O(const T& s){cout<<s<<endl;return 0;} template<typename T>void db(T *bg,T *ed){while(bg!=ed)cout<<*bg++<<' ';pr("\n");} template<typename T>void db(vector<T>&it){for(auto i:it)cout<<i<<' ';pr("\n");} inline ll mul_64(ll x,ll y,ll c){return (x*y-(ll)((long double)x/c*y)*c+c)%c;} inline ll ksm(ll a,ll b,ll c){ll ans=1;for(;b;b>>=1,a=a*a%c)if(b&1)ans=ans*a%c;return ans;} inline void exgcd(ll a,ll b,ll &x,ll &y){if(!b)x=1,y=0;else exgcd(b,a%b,y,x),y-=(a/b)*x;} int main(){ //IN int _;cin>>_; while(_--){ int n;sc("%d",&n); vector<int>y(n,0),p(n,0); int b[3]={0}; string x;cin>>x; for(int i=0;i<n;i++){ if(x[i]=='0')y[i]=0,p[i]=0; else if(x[i]=='2'){ if(b[1])y[i]=0,p[i]=2; else y[i]=1,p[i]=1; } else { if(b[1])y[i]=0,p[i]=1; else y[i]=1,p[i]=0; } b[x[i]-'0']=1; } for(int i=0;i<n;i++)pr("%d",y[i]);O(""); for(int i=0;i<n;i++)pr("%d",p[i]);O(""); } }
D.Carousel
答案只能是1,2,3;去掉末尾和首项相同的元素,如果长度为1就是1,长度偶数或者长度减小了就是2,
否则再找有没有相邻相同的,有就是2,否则就是3.细节处理起来有点麻烦。
#include<bits/stdc++.h> using namespace std; #define me(a,x) memset(a,x,sizeof(a)) #define sc scanf #define pr printf #define IN freopen("in.txt","r",stdin); #define OUT freopen("out.txt","w",stdout); typedef long long ll; typedef unsigned long long ull; const int N=1e6+6; const int mod=1e9+7; template<typename T>int O(const T& s){cout<<s<<endl;return 0;} template<typename T>void db(T *bg,T *ed){while(bg!=ed)cout<<*bg++<<' ';pr("\n");} template<typename T>void db(vector<T>&it){for(auto i:it)cout<<i<<' ';pr("\n");} inline ll mul_64(ll x,ll y,ll c){return (x*y-(ll)((long double)x/c*y)*c+c)%c;} inline ll ksm(ll a,ll b,ll c){ll ans=1;for(;b;b>>=1,a=a*a%c)if(b&1)ans=ans*a%c;return ans;} inline void exgcd(ll a,ll b,ll &x,ll &y){if(!b)x=1,y=0;else exgcd(b,a%b,y,x),y-=(a/b)*x;} int t[N],a[N]; int main(){ //IN int q;cin>>q; while(q--){ int n;sc("%d",&n); for(int i=0;i++<n;sc("%d",&t[i]),a[i]=t[i]); int m=n; while(a[1]==a[m]&&m)m--; if(m<=1){ O(1); for(int i=0;i<n;i++)pr("1 "); O("");continue; } if(n%2==0){ O(2); for(int i=0;i<n;i++)pr("%d ",i%2==0?2:1); O(""); continue; } if(n==m){ int p=0; for(int i=1;i<n;i++){ if(t[i]==t[i+1]){ p=i;break; } } if(p){ O(2); for(int i=1;i<=p;i++)pr("%d ",i%2==0?2:1); if(p&1)pr("1 ");else pr("2 "); for(int i=p+2;i<=n;i++)pr("%d ",i%2==0?1:2); O(""); }else{ O(3); for(int i=1;i<n;i++)pr("%d ",i%2==0?2:1); O(3); } }else{ O(2); for(int i=0;i<n;i++)pr("%d ",i%2==0?1:2); O(""); } } }
E.Tree Queries
这题转化为求k个点是否在一条链上,可以用序判断,对于,两个点,,
他们在一条链上的条件为: ,对深度排序,可以满足这种关系。
或者对于所有节点 。
#include<bits/stdc++.h> using namespace std; #define me(a,x) memset(a,x,sizeof(a)) #define sc scanf #define pr printf #define IN freopen("in.txt","r",stdin); #define OUT freopen("out.txt","w",stdout); typedef long long ll; typedef unsigned long long ull; const int N=2e5+6; const int mod=1e9+7; template<typename T>int O(const T& s){cout<<s<<endl;return 0;} template<typename T>void db(T *bg,T *ed){while(bg!=ed)cout<<*bg++<<' ';pr("\n");} template<typename T>void db(vector<T>&it){for(auto i:it)cout<<i<<' ';pr("\n");} inline ll mul_64(ll x,ll y,ll c){return (x*y-(ll)((long double)x/c*y)*c+c)%c;} inline ll ksm(ll a,ll b,ll c){ll ans=1;for(;b;b>>=1,a=a*a%c)if(b&1)ans=ans*a%c;return ans;} inline void exgcd(ll a,ll b,ll &x,ll &y){if(!b)x=1,y=0;else exgcd(b,a%b,y,x),y-=(a/b)*x;} int k[N],f[N]; int L[N],R[N],t; vector<int>g[N]; int n,m; void dfs(int u,int fa){ f[u]=***]=++t; for(int& v:g[u]){ if(v==fa)continue; dfs(v,u); } R[u]=t; } int main(){ sc("%d%d",&n,&m); for(int i=1;i<n;i++){ int u,v; sc("%d%d",&u,&v); g[u].push_back(v); g[v].push_back(u); } dfs(1,0);f[1]=1; while(m--){ int x;sc("%d",&x); for(int i=0;i++<x;sc("%d",&k[i]),k[i]=f[k[i]]); int mx=n,ma=1; for(int i=1;i<=x;i++)mx=min(mx,R[k[i]]),ma=max(ma,L[k[i]]); int ok=ma<=mx; puts(ok?"YES":"NO"); } }
F.Make k Equal
先排序,枚举当序列都变成时的最小值,分几种情况讨论。
#include<bits/stdc++.h> using namespace std; #define me(a,x) memset(a,x,sizeof(a)) #define sc scanf #define pr printf #define IN freopen("in.txt","r",stdin); #define OUT freopen("out.txt","w",stdout); typedef long long ll; typedef unsigned long long ull; const int N=1e6+6; const int mod=1e9+7; template<typename T>int O(const T& s){cout<<s<<endl;return 0;} template<typename T>void db(T *bg,T *ed){while(bg!=ed)cout<<*bg++<<' ';pr("\n");} template<typename T>void db(vector<T>&it){for(auto i:it)cout<<i<<' ';pr("\n");} inline ll mul_64(ll x,ll y,ll c){return (x*y-(ll)((long double)x/c*y)*c+c)%c;} inline ll ksm(ll a,ll b,ll c){ll ans=1;for(;b;b>>=1,a=a*a%c)if(b&1)ans=ans*a%c;return ans;} inline void exgcd(ll a,ll b,ll &x,ll &y){if(!b)x=1,y=0;else exgcd(b,a%b,y,x),y-=(a/b)*x;} int n,k; int a[N],x=0,cnt=0; ll pre[N],suf[N]; int main(){ cin>>n>>k; for(int i=0;i++<n;sc("%d",&a[i]));sort(a+1,a+1+n); for(int i=1;i<=n;i++)pre[i]=pre[i-1]+a[i]; for(int i=n;i>=1;i--)suf[i]=suf[i+1]+a[i]; for(int i=2;i<=n;i++)if(a[i]==a[i-1])x++;else cnt=max(cnt,x),x=1;cnt=max(cnt,x); if(cnt>=k)return O(0);ll ans=1e18+11; for(int i=1;i<=n;i++){ ll res=1LL*(i-1)*a[i]-pre[i-1]-1LL*a[i]*(n-i)+suf[i+1]-(n-k); if(i>=k)res=min(res,1LL*(i-1)*a[i]-pre[i-1]-(i-k)); if(n-i+1>=k)res=min(res,suf[i+1]-1LL*(n-i)*a[i]-(n-i+1-k)); ans=min(ans,res); } O(ans); }