#include <cstdio>#include <iostream>#include <algorithm>#define N 1007using namespace std;struct Edge{int u,v,w;int id;int operator<(const Edge e)const{if(w!=e.w) return w<e.w;return id>e.id;}}edge[N<<8];int n,m,q;bool ans[N<<7];struct uset{int p[N];uset(int n){for(int i=1;i<=n;i++)p[i]=i;}int find(int x){return x==p[x]?x:p[x]=find(p[x]);}void merge(Edge e){int u=e.u,v=e.v,id=e.id;int fx=find(u),fy=find(v);if(fx!=fy){if(id) ans[id]=1;else p[fx]=fy;}}};void Kruskal(){sort(edge+1,edge+m+q+1); uset us(n);for(int i=1;i<=m+q;i++) us.merge(edge[i]);}int main(){int k,w;for(;cin>>n>>m>>q;){for(int i=1;i<=m;i++)scanf("%d%d%d",&edge[i].u,&edge[i].v,&edge[i].w),edge[i].id=0;for(int i=1;i<=q;i++)scanf("%d%d",&k,&w),edge[m+i]=edge[k],edge[m+i].w=w,edge[m+i].id=i,ans[i]=0;Kruskal();for(int i=1;i<=q;i++)puts(ans[i]?"Yes":"No");}return 0;}
