Submission #1005632

# Submission time Handle Problem Language Result Execution time Memory
1005632 2024-06-22T16:43:51 Z modwwe Tourism (JOI23_tourism) C++17
35 / 100
5000 ms 25940 KB
//https://www.instagram.com/_modwwe/
#pragma GCC optimize("Ofast")
//#pragma GCC target("avx2,bmi,bmi2")
#include<bits/stdc++.h>
//#define int long long
//#define ll long long
#define down cout<<'\n';
#define NHP     ios_base::sync_with_stdio(0);cout.tie(0);cin.tie(0);
#define modwwe  int t;cin>>t; while(t--)
#define bit(i,j) (i>>j&1)
#define sobit(a) __builtin_popcountll(a)
#define task "test"
#define fin(x) freopen(x".inp","r",stdin)
#define fou(x) freopen(x".out","w",stdout)
#define pb push_back
#define checktime   cerr << (double)clock() / CLOCKS_PER_SEC * 1000  << " ms";
using namespace std;
void phongbeo();
const int mod2=1e9+7;
const int  mod1=998244353;
struct icd
{
    int a,b;
};
struct ib
{
    int a;
    int b;
};
struct ic
{
    int a,b,c;
};
struct id
{
    int a,c;
};
struct ie
{
    int a,b,c, d,e,f;

};
int n,m,s1,s2,s4,s3,sf,k,r,mid,s5,s6,mx,s7,s8,s9,mx2,res,dem2=0,dem=0,l;
int  i,s10,s12;
int el=29;
main()
{
//#ifndef ONLINE_JUDGE
     //  fin(task),fou(task);
//#endif
    ios_base::sync_with_stdio(0);cout.tie(0);cin.tie(0);
    /// cin>>s1;
    // modwwe
    phongbeo();
    checktime
}
int t[400007];
int depth[100007];
ic a[100007];
int c[100007];
ib euler[100007];
int d[100007];
int st[17][100007];
int ans[100007];
int S;
int b[100007];
int sl[100007];
vector<int> v[100007];
int e[100007];
int pre[100007];
int nxt[100007];
bool cmp(ic a,ic b)
{
    if(a.a / S != b.a / S) return (a.a < b.a);
    else if(!((a.a / S) & 1)) return (a.b < b.b);
    else return (a.b > b.b);
}
void upd(int node,int l,int r,int l1,int r1,int cc)
{
    if(l>=l1&&r<=r1)
    {
        if(cc==1) t[node]=l;
         else t[node]=0;
        return;
    }
    int mid=l+r>>1;
    if(mid>=r1)
        upd(node<<1,l,mid,l1,r1,cc);
    else
        upd(node<<1|1,mid+1,r,l1,r1,cc);
    t[node]=max(t[node<<1],t[node<<1|1]);
}
int get1(int node,int l,int r,int l1,int r1)
{
    if(l>r1||r<l1) return 0;
    if(l>=l1&&r<=r1) return t[node];

    int mid=l+r>>1;
 int ss3=0;
    if(t[node<<1|1]!=0) ss3=get1(node<<1|1,mid+1,r,l1,r1);
    if(ss3!=0) return ss3;
else return get1(node<<1,l,mid,l1,r1);
}
void dfs(int x,int y)
{
    st[0][x]=y;
    depth[x]=depth[y]+1;
    euler[x].a=++dem;
    mx=max(mx,depth[x]);
    c[dem]=x;
    for(auto f:v[x])
        if(f!=y)
            dfs(f,x);
    euler[x].b=dem;
}
int lca(int x,int y,int cc)
{
    if(x==0||x==n+1||y==0||y==n+1) return 1;
    if(depth[x]<depth[y]) swap(x,y),cc=0;
    int ss=depth[x]-depth[y]-1;
    if(ss>=0)
        for(int j=0; j<mx; ++j)
            if(bit(ss,j))
                x=st[j][x];
    if(st[0][x]==y) return x;
    if(ss!=-1)  x=st[0][x];
    for(int j=mx-1; j>=0; --j)
        if(st[j][x]!=st[j][y])
            x=st[j][x],y=st[j][y];
    if(cc==0) return y;
    else
        return x;
}
int lca2(int x,int y)
{
    if(x==0 )return y;
    if(y==0 )return x;
    if(depth[x]<depth[y]) swap(x,y);
    int ss=depth[x]-depth[y];
    if(ss!=0)
    for(int j=0; j<mx; ++j)
        if(bit(ss,j))
            x=st[j][x];
    if(x==y) return x;
    for(int j=mx-1; j>=0; --j)
        if(st[j][x]!=st[j][y])
            x=st[j][x],y=st[j][y];
    return st[0][x];
}
/*void build2(int node,int l,int r)
{
    if(l==r)
    {
        lz[node]=b[l];
        return;
    }
    int mid=l+r>>1;
    build2(node<<1,l,mid);
    build2(node<<1|1,mid+1,r);
    lz[node]=lca2(lz[node<<1],lz[node<<1|1]);
}
int get_lca(int node,int l,int r,int l1,int r1)
{
    if(l>r1||r<l1) return 0;
    if(l>=l1&&r<=r1) return lz[node];
    int mid=l+r>>1;
    return lca2(get_lca(node<<1,l,mid,l1,r1),get_lca(node<<1|1,mid+1,r,l1,r1));
}*/
void add(int x)
{
    s2=get1(1,1,n,1,euler[x].a);
    /// s3=get2(1,1,n,euler[x].a,n);
    sl[x]++;
    if(sl[x]==1)
    upd(1,1,n,euler[x].a,euler[x].a,1);
    if(d[x]!=0||sl[x]>1) return;
    s2=c[s2];
    s3=nxt[s2];
    pre[x]=s2;
    nxt[x]=s3;
    nxt[s2]=x;
    pre[s3]=x;
//if(l==3&&x==1) cout<<s2<<" "<<s3<<" "<<x,down
    s2=lca(x,s2,1);
    s3=lca(x,s3,1);
    if(depth[s2]<depth[s3]) swap(s2,s3);
    if(depth[x]>=depth[s2])
    {
        s4+=depth[x]-depth[s2]+1;
        d[x]=s2;
        e[s2]=x;
    }
}
void del(int x)
{sl[x]--;
 if(sl[x]==0)
    upd(1,1,n,euler[x].a,euler[x].a,-1);
    s5=d[x];
    //s2=get1(1,1,n,euler[s5].a,euler[x].a);
    //s3=get2(1,1,n,euler[x].a,euler[s5].b);
    if(sl[x]>=1) return;
    s2=pre[x];
    s3=nxt[x];
    nxt[s2]=s3;
    if(s3!=0) pre[s3]=s2;
    pre[x]=0;
    nxt[x]=0;
    s9=s2;
    if(d[x]==0)return;
    d[x]=0;
    e[s5]=0;
    s4-=(depth[x]-depth[s5]+1);
    s2=lca(s2,x,1);
    s3=lca(s3,x,1);
    if(max(depth[s2],depth[s3])<=depth[s5]) return;
    if(st[0][s2]==s9&&depth[s2]>=depth[s3]&&d[s2]==0)
    {
        s2=s9;
        s4+=depth[s2]-depth[s5]+1;
        d[s2]=s5;
        e[s5]=s2;
        return;
    }
    if(depth[s2]<depth[s3])swap(s2,s3);
    if(depth[s5]<depth[s2])
    {
        s3=e[s2];
        e[s2]=0;
        e[s5]=s3;
        d[s3]=s5;
        s4+=(depth[s2]-depth[s5]);
    }
}
void go(int x,int y)
{
    while(r<y)
    {
        ++r;
        add(b[r]);

    }
    while(l>x)
    {
        --l;

        add(b[l]);
        //cout<<l<<" "<<s4,down

    }
    //cout<<s4<<" "<<x<<" "<<y,down
    while(l<x)
    {
        del(b[l]);
        ++l;
    }
    while(r>y)
    {
        del(b[r]);

        --r;
    }

}
int cinn()
{
    char c;
    while (c = getchar(), c < '0' || c > '9');
    int x = c - '0';
    while (c = getchar(), c >= '0' && c <= '9')
        x = x * 10 + c - '0';
    return x;
}
void phongbeo()
{
  cin>>n>>m>>k;
    S=sqrt(m);bool de=0;
    for(int i=1; i<n; ++i){
        cin>>l>>r,v[l].pb(r),v[r].pb(l);
        if(r/2!=l) de=1;}

    dfs(1,0);
        if(!de)mx=5;
else mx=log2(mx)+1;
if(mx>17) mx=17;
    for(int i=1; i<mx; ++i)
        for(int j=1; j<=n; ++j)
            st[i][j]=st[i-1][st[i-1][j]];
    for(int i=1; i<=m; ++i)
        cin>>b[i];
    for(int i=1; i<=k; ++i)
        cin>>a[i].a>>a[i].b,a[i].c=i;
    sort(a+1,a+1+k,cmp);
    l=1;
    r=0;
    for(int i=1; i<=k; ++i)
    {
        go(a[i].a,a[i].b);
        s3=t[1];
        s5=nxt[0];
        s3=c[s3];
        s3=lca2(s3,s5);
        ans[a[i].c]=s4+depth[1]-depth[s3];
    }
    for(int i=1; i<=k; ++i)
        printf("%d",ans[i]),
               printf("\n");
}

/*
8 8 2
1 2
2 3
3 4
4 5
5 6
6 7
7 8
8 6 4 3 5 2 4 7
2 8
1 2

*/

Compilation message

tourism.cpp:46:1: warning: ISO C++ forbids declaration of 'main' with no type [-Wreturn-type]
   46 | main()
      | ^~~~
tourism.cpp: In function 'void upd(int, int, int, int, int, int)':
tourism.cpp:86:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   86 |     int mid=l+r>>1;
      |             ~^~
tourism.cpp: In function 'int get1(int, int, int, int, int)':
tourism.cpp:98:14: warning: suggest parentheses around '+' inside '>>' [-Wparentheses]
   98 |     int mid=l+r>>1;
      |             ~^~
tourism.cpp: In function 'void del(int)':
tourism.cpp:196:2: warning: this 'if' clause does not guard... [-Wmisleading-indentation]
  196 |  if(sl[x]==0)
      |  ^~
tourism.cpp:198:5: note: ...this statement, but the latter is misleadingly indented as if it were guarded by the 'if'
  198 |     s5=d[x];
      |     ^~
# Verdict Execution time Memory Grader output
1 Correct 1 ms 8536 KB Output is correct
2 Correct 1 ms 8536 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 2 ms 8540 KB Output is correct
5 Correct 2 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 2 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 2 ms 8536 KB Output is correct
10 Correct 2 ms 8540 KB Output is correct
11 Correct 2 ms 8540 KB Output is correct
12 Correct 1 ms 8540 KB Output is correct
13 Correct 2 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 2 ms 10588 KB Output is correct
16 Correct 2 ms 10588 KB Output is correct
17 Correct 2 ms 10588 KB Output is correct
18 Correct 2 ms 10588 KB Output is correct
19 Correct 2 ms 10588 KB Output is correct
20 Correct 2 ms 10588 KB Output is correct
21 Correct 2 ms 8540 KB Output is correct
22 Correct 2 ms 8540 KB Output is correct
23 Correct 2 ms 8540 KB Output is correct
24 Correct 2 ms 8540 KB Output is correct
25 Correct 2 ms 8540 KB Output is correct
26 Correct 2 ms 8540 KB Output is correct
27 Correct 1 ms 8540 KB Output is correct
28 Correct 1 ms 8540 KB Output is correct
29 Correct 2 ms 8596 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 8536 KB Output is correct
2 Correct 1 ms 8536 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 2 ms 8540 KB Output is correct
5 Correct 2 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 2 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 2 ms 8536 KB Output is correct
10 Correct 2 ms 8540 KB Output is correct
11 Correct 2 ms 8540 KB Output is correct
12 Correct 1 ms 8540 KB Output is correct
13 Correct 2 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 2 ms 10588 KB Output is correct
16 Correct 2 ms 10588 KB Output is correct
17 Correct 2 ms 10588 KB Output is correct
18 Correct 2 ms 10588 KB Output is correct
19 Correct 2 ms 10588 KB Output is correct
20 Correct 2 ms 10588 KB Output is correct
21 Correct 2 ms 8540 KB Output is correct
22 Correct 2 ms 8540 KB Output is correct
23 Correct 2 ms 8540 KB Output is correct
24 Correct 2 ms 8540 KB Output is correct
25 Correct 2 ms 8540 KB Output is correct
26 Correct 2 ms 8540 KB Output is correct
27 Correct 1 ms 8540 KB Output is correct
28 Correct 1 ms 8540 KB Output is correct
29 Correct 2 ms 8596 KB Output is correct
30 Correct 8 ms 8792 KB Output is correct
31 Correct 9 ms 8792 KB Output is correct
32 Correct 12 ms 8816 KB Output is correct
33 Correct 10 ms 8796 KB Output is correct
34 Correct 11 ms 8792 KB Output is correct
35 Correct 3 ms 8796 KB Output is correct
36 Correct 3 ms 8796 KB Output is correct
37 Correct 3 ms 8796 KB Output is correct
38 Correct 9 ms 13000 KB Output is correct
39 Correct 10 ms 12888 KB Output is correct
40 Correct 9 ms 12892 KB Output is correct
41 Correct 3 ms 12892 KB Output is correct
42 Correct 4 ms 12888 KB Output is correct
43 Correct 4 ms 12892 KB Output is correct
44 Correct 11 ms 10844 KB Output is correct
45 Correct 9 ms 10844 KB Output is correct
46 Correct 10 ms 10844 KB Output is correct
47 Correct 3 ms 10840 KB Output is correct
48 Correct 3 ms 10844 KB Output is correct
49 Correct 3 ms 10912 KB Output is correct
50 Correct 8 ms 8824 KB Output is correct
51 Correct 9 ms 8796 KB Output is correct
52 Correct 8 ms 8796 KB Output is correct
53 Correct 9 ms 8796 KB Output is correct
54 Correct 9 ms 8828 KB Output is correct
55 Correct 8 ms 8796 KB Output is correct
56 Correct 2 ms 8540 KB Output is correct
57 Correct 1 ms 8796 KB Output is correct
58 Correct 3 ms 8796 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 1 ms 8536 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 2 ms 8540 KB Output is correct
4 Correct 2728 ms 20396 KB Output is correct
5 Correct 1971 ms 23304 KB Output is correct
6 Correct 2903 ms 24152 KB Output is correct
7 Correct 4495 ms 25936 KB Output is correct
8 Correct 4592 ms 25840 KB Output is correct
9 Correct 3997 ms 25840 KB Output is correct
10 Correct 4384 ms 25840 KB Output is correct
11 Correct 4285 ms 25796 KB Output is correct
12 Correct 505 ms 25936 KB Output is correct
13 Correct 521 ms 25796 KB Output is correct
14 Correct 535 ms 25940 KB Output is correct
15 Correct 40 ms 24400 KB Output is correct
16 Correct 150 ms 25528 KB Output is correct
17 Correct 123 ms 9912 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 8536 KB Output is correct
2 Correct 71 ms 13404 KB Output is correct
3 Correct 111 ms 13652 KB Output is correct
4 Correct 90 ms 14424 KB Output is correct
5 Correct 60 ms 15904 KB Output is correct
6 Correct 63 ms 15956 KB Output is correct
7 Correct 79 ms 15968 KB Output is correct
8 Correct 88 ms 15952 KB Output is correct
9 Correct 90 ms 15960 KB Output is correct
10 Correct 96 ms 15956 KB Output is correct
11 Correct 130 ms 15980 KB Output is correct
12 Correct 160 ms 15812 KB Output is correct
13 Correct 146 ms 15952 KB Output is correct
14 Correct 141 ms 16320 KB Output is correct
15 Correct 143 ms 17236 KB Output is correct
16 Correct 112 ms 16084 KB Output is correct
17 Correct 126 ms 16012 KB Output is correct
18 Correct 115 ms 16208 KB Output is correct
19 Correct 50 ms 18004 KB Output is correct
20 Correct 56 ms 18024 KB Output is correct
21 Correct 78 ms 18012 KB Output is correct
22 Correct 75 ms 18012 KB Output is correct
23 Correct 77 ms 18008 KB Output is correct
24 Correct 90 ms 18004 KB Output is correct
25 Correct 96 ms 18012 KB Output is correct
26 Correct 103 ms 18000 KB Output is correct
27 Correct 166 ms 18012 KB Output is correct
28 Correct 189 ms 18004 KB Output is correct
29 Correct 196 ms 18040 KB Output is correct
30 Correct 229 ms 18004 KB Output is correct
31 Correct 220 ms 18272 KB Output is correct
32 Correct 217 ms 18252 KB Output is correct
33 Correct 216 ms 18576 KB Output is correct
34 Correct 217 ms 19280 KB Output is correct
# Verdict Execution time Memory Grader output
1 Correct 2 ms 8540 KB Output is correct
2 Correct 1 ms 8540 KB Output is correct
3 Correct 2 ms 8540 KB Output is correct
4 Correct 3509 ms 15216 KB Output is correct
5 Correct 3423 ms 15232 KB Output is correct
6 Correct 4249 ms 16724 KB Output is correct
7 Correct 4463 ms 17536 KB Output is correct
8 Correct 4792 ms 17492 KB Output is correct
9 Execution timed out 5041 ms 16976 KB Time limit exceeded
10 Halted 0 ms 0 KB -
# Verdict Execution time Memory Grader output
1 Correct 1 ms 8536 KB Output is correct
2 Correct 1 ms 8536 KB Output is correct
3 Correct 1 ms 8540 KB Output is correct
4 Correct 2 ms 8540 KB Output is correct
5 Correct 2 ms 8540 KB Output is correct
6 Correct 2 ms 8540 KB Output is correct
7 Correct 2 ms 8540 KB Output is correct
8 Correct 1 ms 8540 KB Output is correct
9 Correct 2 ms 8536 KB Output is correct
10 Correct 2 ms 8540 KB Output is correct
11 Correct 2 ms 8540 KB Output is correct
12 Correct 1 ms 8540 KB Output is correct
13 Correct 2 ms 8540 KB Output is correct
14 Correct 1 ms 8540 KB Output is correct
15 Correct 2 ms 10588 KB Output is correct
16 Correct 2 ms 10588 KB Output is correct
17 Correct 2 ms 10588 KB Output is correct
18 Correct 2 ms 10588 KB Output is correct
19 Correct 2 ms 10588 KB Output is correct
20 Correct 2 ms 10588 KB Output is correct
21 Correct 2 ms 8540 KB Output is correct
22 Correct 2 ms 8540 KB Output is correct
23 Correct 2 ms 8540 KB Output is correct
24 Correct 2 ms 8540 KB Output is correct
25 Correct 2 ms 8540 KB Output is correct
26 Correct 2 ms 8540 KB Output is correct
27 Correct 1 ms 8540 KB Output is correct
28 Correct 1 ms 8540 KB Output is correct
29 Correct 2 ms 8596 KB Output is correct
30 Correct 8 ms 8792 KB Output is correct
31 Correct 9 ms 8792 KB Output is correct
32 Correct 12 ms 8816 KB Output is correct
33 Correct 10 ms 8796 KB Output is correct
34 Correct 11 ms 8792 KB Output is correct
35 Correct 3 ms 8796 KB Output is correct
36 Correct 3 ms 8796 KB Output is correct
37 Correct 3 ms 8796 KB Output is correct
38 Correct 9 ms 13000 KB Output is correct
39 Correct 10 ms 12888 KB Output is correct
40 Correct 9 ms 12892 KB Output is correct
41 Correct 3 ms 12892 KB Output is correct
42 Correct 4 ms 12888 KB Output is correct
43 Correct 4 ms 12892 KB Output is correct
44 Correct 11 ms 10844 KB Output is correct
45 Correct 9 ms 10844 KB Output is correct
46 Correct 10 ms 10844 KB Output is correct
47 Correct 3 ms 10840 KB Output is correct
48 Correct 3 ms 10844 KB Output is correct
49 Correct 3 ms 10912 KB Output is correct
50 Correct 8 ms 8824 KB Output is correct
51 Correct 9 ms 8796 KB Output is correct
52 Correct 8 ms 8796 KB Output is correct
53 Correct 9 ms 8796 KB Output is correct
54 Correct 9 ms 8828 KB Output is correct
55 Correct 8 ms 8796 KB Output is correct
56 Correct 2 ms 8540 KB Output is correct
57 Correct 1 ms 8796 KB Output is correct
58 Correct 3 ms 8796 KB Output is correct
59 Correct 1 ms 8536 KB Output is correct
60 Correct 1 ms 8540 KB Output is correct
61 Correct 2 ms 8540 KB Output is correct
62 Correct 2728 ms 20396 KB Output is correct
63 Correct 1971 ms 23304 KB Output is correct
64 Correct 2903 ms 24152 KB Output is correct
65 Correct 4495 ms 25936 KB Output is correct
66 Correct 4592 ms 25840 KB Output is correct
67 Correct 3997 ms 25840 KB Output is correct
68 Correct 4384 ms 25840 KB Output is correct
69 Correct 4285 ms 25796 KB Output is correct
70 Correct 505 ms 25936 KB Output is correct
71 Correct 521 ms 25796 KB Output is correct
72 Correct 535 ms 25940 KB Output is correct
73 Correct 40 ms 24400 KB Output is correct
74 Correct 150 ms 25528 KB Output is correct
75 Correct 123 ms 9912 KB Output is correct
76 Correct 2 ms 8536 KB Output is correct
77 Correct 71 ms 13404 KB Output is correct
78 Correct 111 ms 13652 KB Output is correct
79 Correct 90 ms 14424 KB Output is correct
80 Correct 60 ms 15904 KB Output is correct
81 Correct 63 ms 15956 KB Output is correct
82 Correct 79 ms 15968 KB Output is correct
83 Correct 88 ms 15952 KB Output is correct
84 Correct 90 ms 15960 KB Output is correct
85 Correct 96 ms 15956 KB Output is correct
86 Correct 130 ms 15980 KB Output is correct
87 Correct 160 ms 15812 KB Output is correct
88 Correct 146 ms 15952 KB Output is correct
89 Correct 141 ms 16320 KB Output is correct
90 Correct 143 ms 17236 KB Output is correct
91 Correct 112 ms 16084 KB Output is correct
92 Correct 126 ms 16012 KB Output is correct
93 Correct 115 ms 16208 KB Output is correct
94 Correct 50 ms 18004 KB Output is correct
95 Correct 56 ms 18024 KB Output is correct
96 Correct 78 ms 18012 KB Output is correct
97 Correct 75 ms 18012 KB Output is correct
98 Correct 77 ms 18008 KB Output is correct
99 Correct 90 ms 18004 KB Output is correct
100 Correct 96 ms 18012 KB Output is correct
101 Correct 103 ms 18000 KB Output is correct
102 Correct 166 ms 18012 KB Output is correct
103 Correct 189 ms 18004 KB Output is correct
104 Correct 196 ms 18040 KB Output is correct
105 Correct 229 ms 18004 KB Output is correct
106 Correct 220 ms 18272 KB Output is correct
107 Correct 217 ms 18252 KB Output is correct
108 Correct 216 ms 18576 KB Output is correct
109 Correct 217 ms 19280 KB Output is correct
110 Correct 2 ms 8540 KB Output is correct
111 Correct 1 ms 8540 KB Output is correct
112 Correct 2 ms 8540 KB Output is correct
113 Correct 3509 ms 15216 KB Output is correct
114 Correct 3423 ms 15232 KB Output is correct
115 Correct 4249 ms 16724 KB Output is correct
116 Correct 4463 ms 17536 KB Output is correct
117 Correct 4792 ms 17492 KB Output is correct
118 Execution timed out 5041 ms 16976 KB Time limit exceeded
119 Halted 0 ms 0 KB -