1 #include<cstdio> 2 #include<iostream> 3 #define M 1000006 4 #define N 1000006 5 using namespace std; 6 int head[N],next[M],u[M],se[N],se1[N],n,m,size[N],l[N],lc[N][22],f1[N],cnt,dui[N],lian[N],tim,l1,l2; 7 int r1; 8 struct data 9 { 10 int l,r,sum,tag; 11 }shu[4*N]; 12 void jia(int a1,int a2) 13 { 14 cnt++; 15 next[cnt]=head[a1]; 16 head[a1]=cnt; 17 u[cnt]=a2; 18 return; 19 } 20 void dfs(int a1) 21 { 22 f1[a1]=1; 23 size[a1]=1; 24 for(int i=1;i<=21;i++) 25 { 26 if(l[a1]<(1>>i)) 27 break; 28 lc[a1][i]=lc[lc[a1][i-1]][i-1]; 29 } 30 for(int i=head[a1];i;i=next[i]) 31 if(!f1[u[i]]) 32 { 33 lc[u[i]][0]=a1; 34 l[u[i]]=l[a1]+1; 35 dfs(u[i]); 36 size[a1]+=size[u[i]]; 37 } 38 return; 39 } 40 void dfs1(int a1,int a2) 41 { 42 tim++; 43 dui[a1]=tim; 44 lian[a1]=a2; 45 int k=0; 46 for(int i=head[a1];i;i=next[i]) 47 if(!dui[u[i]]&&size[k]<size[u[i]]) 48 k=u[i]; 49 if(!k) 50 return; 51 dfs1(k,a2); 52 for(int i=head[a1];i;i=next[i]) 53 if(!dui[u[i]]) 54 dfs1(u[i],u[i]); 55 return; 56 } 57 void geng(int a1) 58 { 59 shu[a1].l=shu[a1*2].l; 60 shu[a1].r=shu[a1*2+1].r; 61 shu[a1].sum=shu[a1*2].sum+shu[a1*2+1].sum; 62 if(shu[a1*2].r==shu[a1*2+1].l) 63 shu[a1].sum--; 64 return; 65 } 66 void build(int a1,int a2,int a3) 67 { 68 if(a2==a3) 69 { 70 shu[a1].sum=1; 71 shu[a1].l=se1[a2]; 72 shu[a1].r=se1[a2]; 73 return; 74 } 75 int mid=(a2+a3)>>1; 76 build(a1*2,a2,mid); 77 build(a1*2+1,mid+1,a3); 78 geng(a1); 79 return; 80 } 81 int lca(int a1,int a2) 82 { 83 if(l[a1]<l[a2]) 84 swap(a1,a2); 85 int a3=l[a1]-l[a2]; 86 for(int i=0;i<=21;i++) 87 if(a3&(1<<i)) 88 a1=lc[a1][i]; 89 for(int i=21;i>=0;i--) 90 if(lc[a1][i]!=lc[a2][i]) 91 { 92 a1=lc[a1][i]; 93 a2=lc[a2][i]; 94 } 95 if(a1==a2) 96 return a1; 97 return lc[a1][0]; 98 } 99 void geng1(int a1) 100 { 101 int a2=shu[a1].l; 102 shu[a1*2].l=a2; 103 shu[a1*2].r=a2; 104 shu[a1*2].sum=1; 105 shu[a1*2].tag=1; 106 shu[a1*2+1].l=a2; 107 shu[a1*2+1].r=a2; 108 shu[a1*2+1].sum=1; 109 shu[a1*2+1].tag=1; 110 shu[a1].tag=0; 111 } 112 void gai1(int a1,int a2,int a3,int a4,int a5,int a6) 113 { 114 if(a4<=a2&&a5>=a3) 115 { 116 shu[a1].l=a6; 117 shu[a1].r=a6; 118 shu[a1].sum=1; 119 shu[a1].tag=1; 120 return; 121 } 122 if(shu[a1].tag) 123 geng1(a1); 124 int mid=(a2+a3)>>1; 125 if(a4<=mid) 126 gai1(a1*2,a2,mid,a4,a5,a6); 127 if(a5>mid) 128 gai1(a1*2+1,mid+1,a3,a4,a5,a6); 129 geng(a1); 130 } 131 void gai(int a1,int t,int a3) 132 { 133 for(;lian[a1]!=lian[t];) 134 { 135 gai1(1,1,n,dui[lian[a1]],dui[a1],a3); 136 a1=lc[lian[a1]][0]; 137 } 138 gai1(1,1,n,dui[t],dui[a1],a3); 139 } 140 int xun1(int a1,int a2,int a3,int a4,int a5) 141 { 142 int ss=0; 143 if(a4<=a2&&a5>=a3) 144 { 145 if(l1==-1) 146 l1=shu[a1].l; 147 r1=shu[a1].r; 148 return shu[a1].sum; 149 } 150 if(shu[a1].tag) 151 geng1(a1); 152 int mid=(a2+a3)>>1; 153 if(a4<=mid) 154 ss+=xun1(a1*2,a2,mid,a4,a5); 155 if(a5>mid) 156 ss+=xun1(a1*2+1,mid+1,a3,a4,a5); 157 if(a4<=mid&&a5>mid&&shu[a1*2].r==shu[a1*2+1].l) 158 ss--; 159 return ss; 160 } 161 int xun(int a1,int t) 162 { 163 int sum=0; 164 l2=-1; 165 for(;lian[a1]!=lian[t];) 166 { 167 l1=-1; 168 sum+=xun1(1,1,n,dui[lian[a1]],dui[a1]); 169 a1=lc[lian[a1]][0]; 170 if(r1==l2) 171 sum--; 172 l2=l1; 173 } 174 l1=-1; 175 sum+=xun1(1,1,n,dui[t],dui[a1]); 176 if(r1==l2) 177 sum--; 178 return sum; 179 } 180 int main() 181 { 182 scanf("%d%d",&n,&m); 183 for(int i=1;i<=n;i++) 184 scanf("%d",&se[i]); 185 for(int i=1;i<n;i++) 186 { 187 int a1,a2; 188 scanf("%d%d",&a1,&a2); 189 jia(a1,a2); 190 jia(a2,a1); 191 } 192 dfs(1); 193 dfs1(1,1); 194 for(int i=1;i<=n;i++) 195 se1[dui[i]]=se[i]; 196 build(1,1,n); 197 char ch[5]; 198 for(int i=1;i<=m;i++) 199 { 200 int a1,a2,a3=0,a5=0; 201 scanf("%s%d%d",ch,&a1,&a2); 202 int t=lca(a1,a2); 203 if(ch[0]=='C') 204 { 205 scanf("%d",&a3); 206 gai(a1,t,a3); 207 gai(a2,t,a3); 208 } 209 else 210 { 211 a3=xun(a1,t); 212 a5=xun(a2,t); 213 a3+=a5; 214 a3--; 215 printf("%d ",a3); 216 } 217 } 218 return 0; 219 }
一个树链剖分，怎么这么长~~~~(>_<)~~~~