Codeforces Round #508 (Div. 2)【A,B,C,D】【实验室日常周赛训练】

 #include<bits/stdc++.h>

 using namespace std;
 #define inf 0x3f3f3f3f3f3f
 #define int long long
 int vis[];
 signed main(){
     int n,k;
     cin>>n>>k;
     string str;
     cin>>str;
     map<int,int> mp;
     int sum=;
     for(int i=;i<str.size();i++){
         if(!mp[str[i]-'A']){
             mp[str[i]-'A']=;
             sum++;
         }
         vis[str[i]-'A']++;
     }
     if(sum==k){
         int ans=inf;
         for(int i=;i<k;i++){
             ans=min(ans,vis[i]);
         }
         //cout<<ans<<'\n';
         cout<<ans*k;
     }else{
         cout<<"";
     }
     return ;
 } 

思路：猜了一个想法，就过了。

 #include<bits/stdc++.h>

 using namespace std;
 #define int long long

 signed main(){
     int n;
     cin>>n;
     if(n==||n==){
         cout<<"No";return ;
     }
     printf("Yes\n");
     int m=n/;
     if(n%){
         int s1=,s2=;
         printf("%lld ",+m);
         for(int i=;i<=n;i+=){
             printf("%lld ",i);
             s1+=i;
         }
         printf("\n");
         printf("%lld ",m);
         for(int i=;i<=n;i+=){
             printf("%lld ",i);
             s2+=i;
         }
         printf("\n");
     //    cout<<__gcd(s1,s2)<<'\n';
     }else{
         int s1=,s2=;
         printf("%lld ",m);
         for(int i=;i<=n;i+=){
             printf("%lld ",i);
             s1+=i;
         }
         printf("\n");
         printf("%lld ",m);
         for(int i=;i<=n;i+=){
             printf("%lld ",i);
             s2+=i;
         }
         printf("\n");
     //    cout<<__gcd(s1,s2)<<'\n';
     }
     return ;
 }
 /*

 */

思路：贪心+模拟【判断应该加自己和移除对手的值哪一个大。优先队列维护最大值】

 #include<bits/stdc++.h>
 using namespace std;
 #define int long long
 #define N 10050005
 priority_queue <int,vector<int>,less<int> >q1;
 priority_queue <int,vector<int>,less<int> >q2;
 int a[N];
 int b[N];
 signed main(){
     int n;cin>>n;
     for(int i=;i<=n;i++){
         cin>>a[i];
         q1.push(a[i]);
     }
     for(int i=;i<=n;i++){
         cin>>b[i];
         q2.push(b[i]);
     }
     int suma=,sumb=;
     int now=;
     while(){
         now++;
         if(q1.empty()&&q2.empty()){
             break;
         }
         int t1=,t2=;
         if(now%){//A
             if(!q1.empty()&&!q2.empty()){
                 t1=q1.top();
                 t2=q2.top();
                 if(t1>t2){
                     q1.pop();
                     suma+=t1;
                 }else{
                     q2.pop();
                 }
             }else if(q1.empty()&&!q2.empty()){
                 q2.pop();
             }else if(!q1.empty()&&q2.empty()){
                 suma+=q1.top();
                 q1.pop();

             }

         }else{
             if(!q1.empty()&&!q2.empty()){
                 t1=q1.top();
                 t2=q2.top();
                 if(t2>t1){
                     q2.pop();
                     sumb+=t2;
                 }else{
                     q1.pop();
                 }
             }else if(q1.empty()&&!q2.empty()){
                 sumb+=q2.top();
                 q2.pop();
             }else if(!q1.empty()&&q2.empty()){
                 q1.pop();
             }

         }
     }
     //cout<<suma<<" "<<sumb<<'\n';
     cout<<suma-sumb;
     return ;
 }

 #include<bits/stdc++.h>

 using namespace std;
 #define int long long
 #define inf 1<<30
 #define N 10005000
 int arr[N];
 signed main(){
     int n;cin>>n;
     if(n==)
     {
         int qwq;
         cin>>qwq;
         cout<<qwq<<endl;return ;
     }
     int flag1=;int flag2=;
     int sum1=;int minx=inf;
     for(int i=;i<=n;i++) {
         cin>>arr[i];
         sum1+=abs(arr[i]);
         if(arr[i]<){
             flag1=;
         }else if(arr[i]>){
             flag2=;
         }
         minx=min(minx,abs(arr[i]));
     }
     if(flag1&&flag2){
         cout<<sum1;
     }else{
         cout<<sum1-abs(minx)*;
     }
     return ;
 }