Wannafly挑战赛3

A 珂朵莉

#include <bits/stdc++.h>

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<typename T> 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<typename A,typename B> inline void read(A&x,B&y){read(x);read(y);}
template<typename A,typename B,typename C> inline void read(A&x,B&y,C&z){read(x);read(y);read(z);}
template<typename A,typename B,typename C,typename D> 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<Max){
			puts("YNOI is good OI!");
			continue;
		}
		int lst=n+1;
		dp[n+2]=0;
		dp[n+1]=0;
		sd[n+2]=0;
		sd[n+1]=0;
		for(int i=n;i>=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
",dp[1]);
	}
	return 0;
}

B 遇见

#include <bits/stdc++.h>
 
using namespace std;
typedef long long ll;
 
template<typename T> 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<typename A,typename B> inline void read(A&x,B&y){read(x);read(y);}
template<typename A,typename B,typename C> inline void read(A&x,B&y,C&z){read(x);read(y);read(z);}
template<typename A,typename B,typename C,typename D> 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
",res,res);
    } else {
        read(x);Mx=Mn=x;
        for(int i=1;i<n;i++){
            read(x);
            Mx=max(x,Mx);
            Mn=min(x,Mn);
        }
        ll r1,r2;
        ll v1=Mx;
        ll v2=Mn;
        r1=(k*18)/((v1+m)*5);
        r2=(k*18)/((v2+m)*5);
        if((k*18)%((v1+m)*5)) r1++;
        if((k*18)%((v2+m)*5)) r2++;
        printf("%lld %lld
",r1,r2);
    }
    return 0;
}

C 位数差

#include <bits/stdc++.h>
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 <bits/stdc++.h>
 
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
",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<<ans<<endl;
    return 0;
}