A 珂朵莉

#include 
    
     using namespace std;typedef long long ll;const int maxn = 1e5+5;double dp[maxn];double sd[maxn];ll a[maxn],n,m;ll s[maxn],x;template
     
       inline void read(T &x){x=0;T f=1;char ch;do{ch=getchar();if(ch=='-')f=-1;}while(ch<'0'||ch>'9');do x=x*10+ch-'0',ch=getchar();while(ch<='9'&&ch>='0');x*=f;}template
      
        inline void read(A&x,B&y){read(x);read(y);}template
       
         inline void read(A&x,B&y,C&z){read(x);read(y);read(z);}template
        
          inline void read(A&x,B&y,C&z,D&w){read(x);read(y);read(z);read(w);}int main(){    //freopen("in.txt","r",stdin);    ll Max=-INT_MAX;    read(n,m);    for(int i=1;i<=n;i++)        read(a[i]),Max=max(Max,a[i]);    s[n+1]=0;    for(int i=n;i;i--)        s[i]=a[i]+s[i+1];    for(int _=1;_<=m;_++){        read(x);        if(x
         
          =1;i--){ while(s[i]-s[lst]>x)lst--; dp[i]=((sd[i+1]-sd[lst+1])*1.0/(lst-i))+1.0; sd[i]=sd[i+1]+dp[i]; } printf("%.2f\n",dp[1]); } return 0;}
         
        
       
      
     
    

B 遇见

#include 
    
      using namespace std;typedef long long ll; template
     
       inline void read(T &x){x=0;T f=1;char ch;do{ch=getchar();if(ch=='-')f=-1;}while(ch<'0'||ch>'9');do x=x*10+ch-'0',ch=getchar();while(ch<='9'&&ch>='0');x*=f;} template
      
        inline void read(A&x,B&y){read(x);read(y);}template
       
         inline void read(A&x,B&y,C&z){read(x);read(y);read(z);}template
        
          inline void read(A&x,B&y,C&z,D&w){read(x);read(y);read(z);read(w);} ll n,m,k;ll Mx,Mn,x;const double eps = 1e-8;int dcmp(double x){    if(x>eps) return 1;    if(x<-eps) return -1;    return 0;} int main(){    //freopen("in.txt","r",stdin);    read(n,m,k);    if(n==0){        ll res = 18ll*k/(5ll*m);        if(18ll*k%(5ll*m)) res++;        printf("%lld %lld\n",res,res);    } else {        read(x);Mx=Mn=x;        for(int i=1;i
        
       
      
     
    

C 位数差

#include 
    
     using namespace std;typedef long long ll;const int N = 1e5 + 5;int sum[N], n, a[N], Rank[N], b[N];ll BIT[15];inline int lowbit(int x) {    return x & (-x);}inline void add(int p) {    while (p < N) {        ++sum[p];        p += lowbit(p);    }}inline int query(int p) {    int res = 0;    while (p) {        res += sum[p];        p -= lowbit(p);    }    return res;}int main() {    ll ans = 0;    scanf("%d", &n);    for (int i = 1; i <= n; ++i) {        scanf("%d", a + i);        b[i] = a[i];    }    sort(b + 1, b + n + 1);    BIT[1] = 0;    BIT[2] = 10;    for (int i = 3; i <= 10; ++i) BIT[i] = BIT[i - 1] * 10;    for (int i = 1; i <= n; ++i) Rank[i] = lower_bound(b + 1, b + n + 1, a[i]) - b;    for (int i = n; i >= 1; --i) {        int now = a[i], bit = 0, flg;        if (!now) bit = 1;        while (now) {            now /= 10;            ++bit;        }        while (1) {            ++bit;            flg = BIT[bit] - a[i];            int DOWN = lower_bound(b + 1, b + n + 1, flg) - b - 1;            if (DOWN == n) break;            ans += query(n + 1) - query(DOWN);        }        add(Rank[i]);    }    cout << ans << endl;    return 0;}
    

D Butterfly2

#include 
    
      using namespace std;typedef long long ll; const int maxn = 505;char mp[maxn][maxn];int n,m;int dp[6][maxn][maxn]; int main(){    //freopen("in.txt","r",stdin);    scanf("%d%d",&n,&m);    for(int i=1;i<=n;i++)        scanf("%s",mp[i]+1);    int ans = 0;    int tmp;    //1    for(int i=1;i<=n;i++){        for(int j=1;j<=m;j++){//left up X            if(mp[i][j]!='X') continue;            dp[0][i][j]=1;            ans=1;            if(i!=1&&j!=1&&mp[i-1][j-1]=='X') dp[0][i][j]=dp[0][i-1][j-1]+1;        }        for(int j=m;j>=1;j--){//right up O            if(mp[i][j]!='O') continue;            dp[1][i][j]=1;            if(i!=1&&j!=m&&mp[i-1][j+1]=='O') dp[1][i][j]=dp[1][i-1][j+1]+1;        }    }    //2    for(int i=n;i>=1;i--){        for(int j=1;j<=m;j++){//left down X            if(mp[i][j]!='X') continue;            dp[2][i][j]=1;            ans=1;            if(i!=n&&j!=1&&mp[i+1][j-1]=='X') dp[2][i][j]=dp[2][i+1][j-1]+1;        }        for(int j=m;j>=1;j--){//right down O            if(mp[i][j]!='O') continue;            dp[3][i][j]=1;            if(i!=n&&j!=m&&mp[i+1][j+1]=='O') dp[3][i][j]=dp[3][i+1][j+1]+1;        }    }         for(int i=1;i<=n;i++){        for(int j=1;j<=m;j++){            if(mp[i][j]!='X') continue;            dp[4][i][j]=1;            if(i!=1&&mp[i-1][j]=='X') dp[4][i][j]=dp[4][i-1][j]+1;        }        for(int j=1;j<=m;j++){            if(mp[i][j]!='O') continue;            dp[5][i][j]=1;            if(i!=1&&mp[i-1][j]=='O') dp[5][i][j]=dp[5][i-1][j]+1;        }    }    // for(int i=1;i<=n;i++)    //  for(int j=1;j<=m;j++)    //      printf("%d\n",dp[0][i][j]);    for(int i=1;i<=n;i++)        for(int j=1;j<=m;j++){            if(i!=1&&i!=n&&j!=1&&j!=m&&mp[i][j]=='X'){                if(mp[i-1][j+1]!='O') continue;                if(mp[i+1][j+1]!='O') continue;                tmp=min(dp[0][i][j],dp[2][i][j]);                tmp=min(tmp,dp[1][i-1][j+1]+1);                tmp=min(tmp,dp[3][i+1][j+1]+1);                for(int k=tmp-1;k>=0;k--){                    if(dp[4][i+k][j-k]>=k+k+1&&dp[5][i+k][j+k]>=k+k+1) ans=max(ans,k+k+1);                }            }        }    cout<
     
      <