Codeforces Gym 101190 NEERC 2016 B. Binary Code

题解

#include
using namespace std;
#define N 500010
#define M 4000000
vector<char>c[N];
vector<int>a[N<<1],g[M];
int num,nx[N<<1][2],w[N<<1],w2[N<<1];
int i,j,k,n,m,p,pos[N],pr[N<<1],sf[N<<1],l;
int Rt=1;
char s[N];
inline void Insert(int& x,int y,int z){
    if(!x)x=++num;
    if(y==l){
        a[x].push_back(z);
        return;
    }
    Insert(nx[x][s[y]-'0'],y+1,z);
}
inline void Build(int x,int y,int z){
    if(!x)return;
    int X=++num,Y=++num;
    if(a[x].size()==0){
        pr[x]=X;sf[x]=Y;
    }else{
        pr[x]=++num;sf[x]=++num;
        for(int i=0;i1);
            if(!i)g[pr[x]].push_back(num);else g[w[a[x][i-1]]].push_back(num);
            if(i==(int)a[x].size()-1)g[num].push_back(X);
            w2[a[x][i]]=++num;g[num].push_back(a[x][i]^1);
        }
        for(int i=0;iif(i==(int)a[x].size()-1)g[Y].push_back(w2[a[x][i]]),g[a[x][i]].push_back(X);
            else g[a[x][i]].push_back(w[a[x][i+1]]),g[w2[a[x][i+1]]].push_back(w2[a[x][i]]);
            if(!i)g[w2[a[x][i]]].push_back(sf[x]),g[a[x][i]].push_back(sf[x]);else g[a[x][i]].push_back(w2[a[x][i-1]]);
        }
    }
    if(y)g[y].push_back(pr[x]),g[sf[x]].push_back(z);
    Build(nx[x][0],X,Y);Build(nx[x][1],X,Y);
}
bool b[M];
int cnt;
int f[M],dfn[M],low[M],T,st[M],top;
inline void Dfs(int x){
    dfn[x]=low[x]=++T;st[++top]=x;
    for(int i=0;iint v=g[x][i];
        if(!dfn[v])Dfs(v),low[x]=min(low[x],low[v]);else
        if(!f[v])low[x]=min(low[x],dfn[v]);
    }
    if(low[x]==dfn[x]){
        ++cnt;
        while(st[top]!=x)f[st[top--]]=cnt;
        f[st[top--]]=cnt;
    }
}
inline bool Tarjan(){
    for(int i=2;i<=num;i++)
    if(!dfn[i])Dfs(i);
    for(int i=1;i<=n;i++)
    if(f[i<<1]==f[i<<1|1])return 0;
    return 1;
}
int main(){
    freopen("binary.in","r",stdin);
    freopen("binary.out","w",stdout);
    scanf("%d",&n);
    memset(pos,-1,sizeof(pos));num=n<<1|1;
    for(i=1;i<=n;i++){
        scanf("%s",s);l=strlen(s);
        for(j=0;jif(s[j]=='?')pos[i]=j;
            c[i].push_back(s[j]);
        }
        if(pos[i]==-1)Insert(Rt,0,i<<1|1),g[i<<1].push_back(i<<1|1);else{
            s[pos[i]]='0';Insert(Rt,0,i<<1|1);
            s[pos[i]]='1';Insert(Rt,0,i<<1);
        }
    }
    Build(1,0,0);
    if(!Tarjan())puts("NO");else{
        puts("YES");
        for(i=1;i<=n;i++){
            for(j=0;jif(c[i][j]=='?')putchar((f[i<<1]1|1])+'0');else putchar(c[i][j]);
            putchar('\n');
        }
    }
    return 0;
}