题解Here!

#include<iostream>
#include<algorithm>
#include<cstdio>
#include<cmath>
#include<cstring>
#define MAXN 100010
#define MAXM 20
using namespace std;
int n,m;
double fact[MAXM],val[MAXN][MAXM];
int top,stack[MAXN];
struct Link_Cut_Tree{int f,flag,son[2];double v[MAXM];
}a[MAXN];
inline int read(){int date=0,w=1;char c=0;while(c<'0'||c>'9'){if(c=='-')w=-1;c=getchar();}while(c>='0'&&c<='9'){date=date*10+c-'0';c=getchar();}return date*w;
}
inline bool isroot(int rt){return a[a[rt].f].son[0]!=rt&&a[a[rt].f].son[1]!=rt;
}
inline void pushup(int rt){if(!rt)return;for(int i=0;i<=15;i++)a[rt].v[i]=a[a[rt].son[0]].v[i]+a[a[rt].son[1]].v[i]+val[rt][i];
}
inline void pushdown(int rt){if(!rt||!a[rt].flag)return;a[a[rt].son[0]].flag^=1;a[a[rt].son[1]].flag^=1;a[rt].flag^=1;swap(a[rt].son[0],a[rt].son[1]);
}
inline void turn(int rt){int x=a[rt].f,y=a[x].f,k=a[x].son[0]==rt?1:0;if(!isroot(x)){if(a[y].son[0]==x)a[y].son[0]=rt;else a[y].son[1]=rt;}a[rt].f=y;a[x].f=rt;a[a[rt].son[k]].f=x;a[x].son[k^1]=a[rt].son[k];a[rt].son[k]=x;pushup(x);pushup(rt);
}
void splay(int rt){top=0;stack[++top]=rt;for(int i=rt;!isroot(i);i=a[i].f)stack[++top]=a[i].f;while(top)pushdown(stack[top--]);while(!isroot(rt)){int x=a[rt].f,y=a[x].f;if(!isroot(x)){if((a[y].son[0]==x)^(a[x].son[0]==rt))turn(rt);else turn(x);}turn(rt);}
}
void access(int rt){for(int i=0;rt;i=rt,rt=a[rt].f){splay(rt);a[rt].son[1]=i;pushup(rt);}
}
inline void makeroot(int rt){access(rt);splay(rt);a[rt].flag^=1;}
int findroot(int rt){access(rt);splay(rt);while(a[rt].son[0])rt=a[rt].son[0];return rt;
}
inline void split(int x,int y){makeroot(x);access(y);splay(y);}
inline void link(int x,int y){makeroot(x);a[x].f=y;}
inline void cut(int x,int y){split(x,y);if(a[y].son[0]==x&&a[x].f==y&&!a[x].son[1])a[x].f=a[y].son[0]=0;
}
void change(int x,int f,double a,double b){memset(val[x],0,sizeof(val[x]));if(f==1){double t=1,Sin=sin(b),Cos=cos(b);for(int i=0;i<=15;i++){val[x][i]=((i%2)?Cos:Sin)*((i%4<=1)?1:-1)*t/fact[i];t*=a;}}else if(f==2){double t=1,Exp=exp(b);for(int i=0;i<=15;i++){val[x][i]=Exp*t/fact[i];t*=a;}}else{val[x][0]=b;val[x][1]=a;}
}
double query(int x,int y,double k){split(x,y);double s=0,t=1;for(int i=0;i<=15;i++){s+=a[y].v[i]*t;t*=k;}return s;
}
void work(){int u,v;double x,y,k;char ch[20];while(m--){scanf("%s",ch);u=read();v=read();switch(ch[0]){case 'a':{u++;v++;link(u,v);break;}case 'd':{u++;v++;cut(u,v);break;}case 'm':{u++;access(u);splay(u);scanf("%lf%lf",&x,&y);change(u,v,x,y);pushup(u);break;}case 't':{u++;v++;scanf("%lf",&k);if(findroot(u)!=findroot(v))printf("unreachable\n");else printf("%.8e\n",query(u,v,k));break;}}}
}
void init(){int f;double x,y;char ch[5];n=read();m=read();scanf("%s",ch);fact[0]=1;for(int i=1;i<=16;i++)fact[i]=fact[i-1]*i;for(int i=1;i<=n;i++){f=read();scanf("%lf%lf",&x,&y);change(i,f,x,y);}
}
int main(){init();work();return 0;
}