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#include<cstdio>
#include<cstring>
#include<algorithm>
#include<iostream>
#include<queue>
#include<map>
#include<stack>
#include<cmath>
#include<set>
#include<bitset>
#include<complex>
#include<assert.h>
#define inc(i,l,r) for(int i=l;i<=r;i++)
#define dec(i,l,r) for(int i=l;i>=r;i--)
#define link(x) for(edge *j=h[x];j;j=j->next)
#define mem(a) memset(a,0,sizeof(a))
#define ll long long
#define eps 1e-8
#define succ(x) (1<<x)
#define mid (x+y>>1)
#define lowbit(x) (x&(-x))
#define sqr(x) ((x)*(x))
#define NM 200005
#define nm 400005
using namespace std;
const double pi=acos(-1);
const ll inf=1e18;
ll read(){
ll x=0,f=1;char ch=getchar();
while(!isdigit(ch)){if(ch=='-')f=-1;ch=getchar();}
while(isdigit(ch))x=x*10+ch-'0',ch=getchar();
return f*x;
}
struct edge{int t;ll v;edge*next;}e[nm],*h[NM],*o=e;
void add(int x,int y,ll v){o->t=y;o->v=v;o->next=h[x];h[x]=o++;}
int n,m,g[NM],_g[NM],_x,_y,id[NM],S,T,tot,a[NM],p[NM];
ll d[NM],_d[NM],_t;
struct tmp{
int x;ll d;
bool operator<(const tmp&o)const{return d>o.d;}
};
priority_queue<tmp>q;
void dij(int u){
inc(i,1,n)d[i]=inf;
q.push(tmp{u,d[u]=0});
while(!q.empty()){
int t=q.top().x;q.pop();
link(t)if(d[j->t]>d[t]+j->v)q.push(tmp{j->t,d[j->t]=d[t]+j->v}),p[j->t]=t;
}
}
void dfs(int x){
link(x)if(!g[j->t]&&d[j->t]==d[x]+j->v)g[j->t]=g[x],dfs(j->t);
}
struct node{
int x,y;ll s;
node*l,*r;
node(int x,int y,node*l=0,node*r=0):x(x),y(y),l(l),r(r),s(inf){}
void push(){l->s=min(l->s,s);r->s=min(r->s,s);}
void mod(){
if(_y<x||y<_x)return;
if(_x<=x&&y<=_y){s=min(s,_t);return;}
l->mod();r->mod();
}
void out(){
if(x==y){_d[x]=s;return;}
push();l->out();r->out();
}
}*root;
node*build(int x,int y){return x==y?new node(x,y):new node(x,y,build(x,mid),build(mid+1,y));}
int main(){
n=read();m=read();
inc(i,1,m){_x=read();_y=read();_t=read();add(_x,_y,_t);add(_y,_x,_t);}
S=read();T=read();
if(S==T)goto la;
dij(S);
for(int x=T;x!=S;x=p[x]){
id[x]=++tot;a[tot]=x;
}
id[S]=++tot;a[tot]=S;
dec(i,tot,1)g[a[i]]=a[i];
dec(i,tot,1)dfs(a[i]);
inc(i,1,n)_d[i]=d[i];
inc(i,1,n)_g[i]=g[i];
dij(T);mem(g);
inc(i,1,tot)g[a[i]]=a[i];
inc(i,1,tot)dfs(a[i]);
root=build(1,tot-1);
inc(i,1,n)link(i)if(!id[i]||!id[j->t]||abs(d[i]-d[j->t])<+j->v){
_x=id[g[j->t]];_y=id[_g[i]]-1;_t=_d[i]+d[j->t]+j->v;
if(_x>_y)continue;
root->mod();
}
inc(i,1,tot-1)_d[i]=inf;
root->out();
la:
m=read();while(m--){
_x=read();_y=read();
if(id[_x]&&id[_y]&&abs(id[_x]-id[_y])==1){
if(_d[min(id[_x],id[_y])]<inf)printf("%lld\n",_d[min(id[_x],id[_y])]);
else printf("Infinity\n");
}else{
if(d[S]<inf)printf("%lld\n",d[S]);else printf("Infinity\n");
}
}
return 0;
}
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