#pragma GCC optimize("O2,Ofast,inline,unroll-all-loops,-ffast-math")
#pragma GCC target("avx,sse2,sse3,sse4,popcnt")
#include<bits/stdc++.h>
#define reg register int
#define il inline
#define fi first
#define se second
#define mk(a,b) make_pair(a,b)
#define numb (ch^'0')
using namespace std;
typedef long long ll;
template<class T>il void rd(T &x){char ch;x=0;bool fl=false;while(!isdigit(ch=getchar()))(ch=='-')&&(fl=true);for(x=numb;isdigit(ch=getchar());x=x*10+numb);(fl==true)&&(x=-x);
}
template<class T>il void output(T x){if(x/10)output(x/10);putchar(x%10+'0');}
template<class T>il void ot(T x){if(x<0) putchar('-'),x=-x;output(x);putchar(' ');}
template<class T>il void prt(T a[],int st,int nd){for(reg i=st;i<=nd;++i) ot(a[i]);putchar('\n');}namespace Miracle{
const int N=150000+5;
const int inf=0x3f3f3f3f;
int n,q,A;
int age[N];
struct node{int nxt,to,val;
}e[2*N];
int hd[N],cnt;
void add(int x,int y,int z){e[++cnt].nxt=hd[x];e[cnt].to=y;e[cnt].val=z;hd[x]=cnt;
}
int sz[N],nowsz;
struct po{int id,dis;ll bac;po(){}po(int dd,int ds){id=dd;dis=ds;bac=ds;}bool friend operator <(po a,po b){if(a.id!=b.id) return a.id<b.id;return a.dis<b.dis;}void op(){cout<<" id "<<id<<" dis "<<dis<<" bac "<<bac<<endl;}
};
vector<po>mem[N];
int dis[N][19];
int fa[N];
vector<po>df[N];
int rt;//,sz[N];
int vis[N];
int dep[N];
void fin(int x,int fa){sz[x]=1;int mxsz=0;for(reg i=hd[x];i;i=e[i].nxt){int y=e[i].to;if(y==fa||vis[y]) continue;fin(y,x);sz[x]+=sz[y];mxsz=max(mxsz,sz[y]);}mxsz=max(mxsz,nowsz-sz[x]);if(mxsz<=nowsz/2){rt=x;}
}
void dfs2(int x,int fa,int d){sz[x]=1;if(d!=1) df[rt].push_back(po(age[x],dis[x][d-1]));mem[rt].push_back(po(age[x],dis[x][d]));for(reg i=hd[x];i;i=e[i].nxt){int y=e[i].to;if(y==fa||vis[y]) continue;dis[y][d]=dis[x][d]+e[i].val;dfs2(y,x,d);sz[x]+=sz[y];}
}
void divi(int x,int d,int f){
//    cout<<" divi "<<x<<" d "<<d<<" f "<<f<<" nowsz "<<nowsz<<endl;rt=0;fin(x,0);
//    cout<<" rt "<<rt<<endl;dep[rt]=d;fa[rt]=f;dfs2(rt,0,d);if(d!=1){sort(df[rt].begin(),df[rt].end());for(reg i=df[rt].size()-2;i>=0;--i){df[rt][i].bac=df[rt][i+1].bac+df[rt][i].dis;}}sort(mem[rt].begin(),mem[rt].end());for(reg i=mem[rt].size()-2;i>=0;--i){mem[rt][i].bac=mem[rt][i+1].bac+mem[rt][i].dis;}vis[rt]=1;int tmp=rt;for(reg i=hd[tmp];i;i=e[i].nxt){int y=e[i].to;if(!vis[y]){nowsz=sz[y];divi(y,d+1,tmp);}}
}
ll wrk(int x,int L,int R){ll ret=0;int le=lower_bound(mem[x].begin(),mem[x].end(),po(L,-1))-mem[x].begin();int ri=upper_bound(mem[x].begin(),mem[x].end(),po(R,inf))-mem[x].begin();if(le!=mem[x].size()) ret+=mem[x][le].bac;if(ri!=mem[x].size()) ret-=mem[x][ri].bac;
//    cout<<"start "<<ret<<endl;int st=x;while(fa[x]){int y=fa[x];
//        cout<<" yy "<<y<<" dis "<<dis[st][dep[y]]<<endl;
//        for(reg i=0;i<mem[y].size();++i){
//            cout<<" i "<<i+1;mem[y][i].op();cout<<endl;
//        }int le=lower_bound(mem[y].begin(),mem[y].end(),po(L,-1))-mem[y].begin();int ri=upper_bound(mem[y].begin(),mem[y].end(),po(R,inf))-mem[y].begin();
//        cout<<" le ri "<<le<<" "<<ri<<endl;if(le!=mem[y].size()) ret+=mem[y][le].bac,ret+=(ll)(mem[y].size()-le)*dis[st][dep[y]];if(ri!=mem[y].size()) ret-=mem[y][ri].bac,ret-=(ll)(mem[y].size()-ri)*dis[st][dep[y]];
//        cout<<" ret before dele "<<ret<<endl;le=lower_bound(df[x].begin(),df[x].end(),po(L,-1))-df[x].begin();ri=upper_bound(df[x].begin(),df[x].end(),po(R,inf))-df[x].begin();if(le!=df[x].size()) ret-=df[x][le].bac,ret-=(ll)(df[x].size()-le)*dis[st][dep[y]];if(ri!=df[x].size()) ret+=df[x][ri].bac,ret+=(ll)(df[x].size()-ri)*dis[st][dep[y]];        x=fa[x];}return ret;
}
int main(){rd(n);rd(q);rd(A);for(reg i=1;i<=n;++i) rd(age[i]);int x,y,z;for(reg i=1;i<n;++i){rd(x);rd(y);rd(z);add(x,y,z);add(y,x,z);}nowsz=n;divi(1,1,0);ll ans=0;int a,b,L,R;while(q--){rd(x);rd(a);rd(b);L=min((a+ans)%A,(b+ans)%A),R=max((a+ans)%A,(b+ans)%A);
//        cout<<" true "<<x<<" "<<L<<" "<<R<<endl;printf("%lld\n",ans=wrk(x,L,R));}return 0;
}}
signed main(){Miracle::main();return 0;
}/*Author: *Miracle*Date: 2019/3/23 19:57:03
*/