Codeforces Beta Round #75 (Div. 2 Only)

Codeforces Beta Round #75 (Div. 2 Only)

http://codeforces.com/contest/92

A

 #include<iostream>
 using namespace std;
 #define lson l,mid,rt<<1
 #define rson mid+1,r,rt<<1|1
 #define sqr(x) ((x)*(x))
 #define maxn 100005
 typedef long long ll;
 typedef unsigned long long ull;
 const ull MOD=;
 /*#ifndef ONLINE_JUDGE
         freopen("1.txt","r",stdin);
 #endif */

 int main(){
     #ifndef ONLINE_JUDGE
      //   freopen("1.txt","r",stdin);
     #endif
     std::ios::sync_with_stdio(false);
     int n,m;
     cin>>n>>m;
     int i=;
     while(i+<=m){
         m-=i+;
         i++;
         if(i==n) i%=n;
     }
     cout<<m<<endl;
 }

B

模拟+找规律

 #include<iostream>
 using namespace std;
 #define lson l,mid,rt<<1
 #define rson mid+1,r,rt<<1|1
 #define sqr(x) ((x)*(x))
 #define maxn 100005
 typedef long long ll;
 typedef unsigned long long ull;
 const ull MOD=;
 /*#ifndef ONLINE_JUDGE
         freopen("1.txt","r",stdin);
 #endif */

 ///

 int main(){
     #ifndef ONLINE_JUDGE
      //   freopen("1.txt","r",stdin);
     #endif
     std::ios::sync_with_stdio(false);
     string str;
     cin>>str;
     if(str==""){
         cout<<;
         return ;
     }
     int ans=;
     for(int i=str.length()-;i>=;i--){
         if(str[i]==''&&i==) break;
         if(str[i]==''){
             ans+=;
             int l=i;
             while(l>=&&str[l]==''){
                 str[l]='';
                 l--;
             }
             if(l>=) str[l]='';
         }
         else{
             ans++;
         }

     }
     cout<<ans<<endl;
 }

C

二分

 #include<bits/stdc++.h>
 using namespace std;
 #define lson l,mid,rt<<1
 #define rson mid+1,r,rt<<1|1
 #define sqr(x) ((x)*(x))
 #define pb push_back
 #define eb emplace_back
 #define maxn 1000006
 #define eps 1e-8
 #define pi acos(-1.0)
 #define rep(k,i,j) for(int k=i;k<j;k++)
 typedef long long ll;
 typedef pair<int,int> pii;
 typedef pair<char,int> pci;
 typedef pair<pair<int,string>,pii> ppp;
 typedef unsigned long long ull;
 /*#ifndef ONLINE_JUDGE
         freopen("1.txt","r",stdin);
 #endif */

 vector<int>ve[];
 int book[];

 int main(){
     #ifndef ONLINE_JUDGE
      //   freopen("1.txt","r",stdin);
     #endif
     std::ios::sync_with_stdio(false);
     string s1,s2;
     cin>>s1>>s2;
     int ans=;
     for(int i=;i<s1.length();i++){
         ve[s1[i]-'a'].pb(i);
     }
     int pos=-;
     int x,tmp;
     for(int i=;i<s2.length();i++){
         x=s2[i]-'a';
         if(ve[x].size()==){
             cout<<-<<endl;
             return ;
         }
         tmp=lower_bound(ve[x].begin(),ve[x].end(),pos+)-ve[x].begin();
         if(tmp!=ve[x].size()){
             pos=ve[x][tmp];
         }
         else{
             ans++;
             pos=lower_bound(ve[x].begin(),ve[x].end(),)-ve[x].begin();
             pos=ve[x][pos];
         }
      //   cout<<tmp<<" "<<pos<<" "<<ans<<endl;
       //  cout<<pos<<endl;
     }
     cout<<ans<<endl;
 }

D

线段树

 #include<bits/stdc++.h>
 using namespace std;
 #define lson l,mid,rt<<1
 #define rson mid+1,r,rt<<1|1
 #define sqr(x) ((x)*(x))
 #define pb push_back
 #define eb emplace_back
 #define maxn 100005
 #define eps 1e-8
 #define pi acos(-1.0)
 #define rep(k,i,j) for(int k=i;k<j;k++)
 typedef long long ll;
 typedef pair<int,int> pii;
 typedef pair<char,int> pci;
 typedef pair<pair<int,string>,pii> ppp;
 typedef unsigned long long ull;
 /*#ifndef ONLINE_JUDGE
         freopen("1.txt","r",stdin);
 #endif */

 int a[maxn];
 int tree[maxn<<];
 int n;

 void push_up(int rt){
     tree[rt]=min(tree[rt<<],tree[rt<<|]);
 }

 void build(int l,int r,int rt){
     if(l==r){
         tree[rt]=a[l];
         return;
     }
     int mid=l+r>>;
     build(lson);
     build(rson);
     push_up(rt);
 }

 int query(int L,int R,int v,int l,int r,int rt){
     if(l==r&&L<=l&&R>=r){
         return l;
     }
     int mid=l+r>>;
     if(L<=mid&&tree[rt<<]<v){
         return query(L,R,v,lson);
     }
     else if(R>mid&&tree[rt<<|]<v){
         return query(L,R,v,rson);
     }
     return -;
 }

 int main(){
     #ifndef ONLINE_JUDGE
      //   freopen("1.txt","r",stdin);
     #endif
     std::ios::sync_with_stdio(false);
     cin>>n;
     for(int i=n;i>=;i--) cin>>a[i];
     build(,n,);
     int pos;
     vector<int>ans;
     for(int i=;i<=n;i++){
         pos=query(,i,a[i],,n,);
         if(pos==-) ans.pb(pos);
         else ans.pb(i-pos-);
     }
     reverse(ans.begin(),ans.end());
     for(int i=;i<ans.size();i++) cout<<ans[i]<<" ";
 }

E

并查集

 #include<bits/stdc++.h>
 using namespace std;
 #define lson l,mid,rt<<1
 #define rson mid+1,r,rt<<1|1
 #define sqr(x) ((x)*(x))
 #define pb push_back
 #define eb emplace_back
 #define maxn 100005
 #define eps 1e-8
 #define pi acos(-1.0)
 #define rep(k,i,j) for(int k=i;k<j;k++)
 typedef long long ll;
 typedef pair<int,int> pii;
 typedef pair<char,int> pci;
 typedef pair<pair<int,string>,pii> ppp;
 typedef unsigned long long ull;
 const long long MOD=1e9+;
 /*#ifndef ONLINE_JUDGE
         freopen("1.txt","r",stdin);
 #endif */

 int n,m;
 int fa[];

 int Find(int x){
     int r=x,y;
     while(x!=fa[x]) x=fa[x];
     while(r!=x){
         y=fa[r];
         fa[r]=x;
         r=y;
     }
     return x;
 }

 int main(){
     #ifndef ONLINE_JUDGE
      //   freopen("1.txt","r",stdin);
     #endif
     std::ios::sync_with_stdio(false);
     cin>>n>>m;
     int x,y,xx,yy;
     ll ans=;
     for(int i=;i<=n;i++) fa[i]=i;
     for(int i=;i<m;i++){
         cin>>x>>y;
         xx=Find(x),yy=Find(y);
         if(xx==yy){
             ans=(ans+ans)%MOD;
         }
         else fa[xx]=yy;
         cout<<ans-<<endl;
     }

 }