SDOI2011 染色

来源：互联网发布：python入门经典答案编辑：程序博客网时间：2024/04/27 09:49
先知道是树剖后一下子就想出来了。。。。。。应该不难的，但是代码写得有点长，调了好久。。。。。。。
还要感谢段大神帮我调出来了^-^是query写错了，在fu == fv的时候，没有处理好标记ＱＡＱ
here is my program
#include<cstdio>#include<cstdlib>#include<cstring>#include<iostream>#include<algorithm>#include<vector>using namespace std;#define lc (o<<1)#define rc (o<<1|1)#define pb push_back#define For(i, a, b) for(int i = (a); i <= (int)(b); i++)#define MAXN (100000+5)int n, ql, qr, dfsn, cp;int rco[MAXN], fa[MAXN], siz[MAXN], top[MAXN], son[MAXN], dep[MAXN], w[MAXN], co[MAXN];vector<int> G[MAXN];struct node{    int st, en, cnt;    node(){        st = en = cnt = 0;    }    node operator +(const node &rhs)const{        if(!rhs.st && !rhs.en && !rhs.cnt) return *this;        if(!st && !en && !cnt) return rhs;        node ret;        ret.cnt = cnt+rhs.cnt;        if(en == rhs.st) ret.cnt--;        ret.st = st; ret.en = rhs.en;        return ret;    }    void print(){        printf("%d %d %d\n", st, en, cnt);    }};struct Seg_tree{    node inf[MAXN*4];     int bj[MAXN*4];    inline void pushdown(int o){        if(!bj[o]) return;                    bj[o] = false; bj[lc] = bj[rc] = true;        inf[lc].st = inf[rc].st = inf[lc].en = inf[rc].en = inf[o].st;        inf[lc].cnt = inf[rc].cnt = inf[o].cnt;    }    inline void maintain(int o){        inf[o] = inf[lc]+inf[rc];    }    inline void build(int o, int L, int R){        if(L == R){            ++cp;            inf[o].st = inf[o].en = rco[cp]; inf[o].cnt = 1;            return;        }                                                                                                                                                                                                                                                                                                                int mid = (L+R)>>1;        build(lc, L, mid); build(rc, mid+1, R);        maintain(o);    }    inline void modify(int o, int L, int R, int col){        if(ql <= L && qr >= R){            inf[o].st = inf[o].en = col; inf[o].cnt = 1; bj[o] = true;            return;        }        pushdown(o);        int mid = (L+R)>>1;        if(ql <= mid) modify(lc, L, mid, col);        if(qr > mid) modify(rc, mid+1, R, col);        maintain(o);    }    inline node query(int o, int L, int R){        if(ql <= L && qr >= R) return inf[o];                        pushdown(o);        int mid = (L+R)>>1;        if(qr <= mid) return query(lc, L, mid);        else if(ql > mid) return query(rc, mid+1, R);        else return query(lc, L, mid)+query(rc, mid+1, R);    }}ST;void dfs1(int now, int La, int D){    fa[now] = La; siz[now] = 1; dep[now] = D;        int maxw = 0;    For(i, 0, G[now].size()-1){        int v = G[now][i];        if(v == La) continue;        dfs1(v, now, D+1);        siz[now] += siz[v];        if(siz[v] > maxw) maxw = siz[v], son[now] = v;    }}void dfs2(int now, int Top){    top[now] = Top; w[now] = ++dfsn;    int v;    if(son[now]) dfs2(son[now], Top);    For(i, 0, G[now].size()-1){        v = G[now][i];        if(v == son[now] || v == fa[now]) continue;        dfs2(v, v);    }}void update(int u, int v, int col){    while(u != v){        int fu = top[u], fv = top[v];        if(dep[fu] < dep[fv]){            swap(u, v); swap(fu, fv);        }        if(fu == fv){            ql = min(w[u], w[v]); qr = w[u]+w[v]-ql;            ST.modify(1, 1, n, col);            break;        }        ql = w[fu]; qr = w[u];        ST.modify(1, 1, n, col);        u = fa[fu];    }    if(u == v){        ql = qr = w[u];        ST.modify(1, 1, n, col);    }}void query(int u, int v){    node tu, tv;    while(u != v){        int fu = top[u], fv = top[v];        if(dep[fu] < dep[fv]){            swap(u, v); swap(fu, fv); swap(tu, tv);        }        if(fu == fv){            ql = min(w[u], w[v]); qr = w[u]+w[v]-ql;            if(ql == w[u]) tv = ST.query(1, 1, n)+tv;            else tu = ST.query(1, 1, n)+tu;            break;        }        ql = w[fu]; qr = w[u];        tu = ST.query(1, 1, n)+tu;        u = fa[fu];    }    if(u == v){        ql = qr = w[u];        tu = ST.query(1, 1, n)+tu;    }        int ans = tu.cnt+tv.cnt;    if(tu.st == tv.st) ans--;    printf("%d\n", ans);} int main(){    int m;    scanf("%d%d", &n, &m);    For(i, 1, n) scanf("%d", &co[i]);    For(i, 1, n-1){        int x, y;        scanf("%d%d", &x, &y);        G[x].pb(y); G[y].pb(x);        }         dfs1(1, 0, 1); dfs2(1, 1);    For(i, 1, n) rco[w[i]] = co[i];    ST.build(1, 1, n);    char s[5];    int a, b, c;    while(m--){        scanf("%s", s);        if(s[0] == 'C'){            scanf("%d%d%d", &a, &b, &c);               update(a, b, c);         }else{            scanf("%d%d", &a, &b);            if(a != b) query(a, b);            else printf("1\n");        }    }            return 0;}
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