#include <cstdio>
#include <algorithm>
#include <set>
#include <vector>
#include <cstring>  #define setI(s) freopen(s".in","r",stdin)
#define setO(s) freopen(s".out","w",stdout)
#define setIO(s) setI(s),setO(s)  using namespace std;   const int N=2e5+5;
const int inf=1e9+2;                     namespace lct {  #define lson s[x].ch[0] #define rson s[x].ch[1] struct data {int ch[2],rev,val,mi,f;         data(int x=inf) { ch[0]=ch[1]=0,val=mi=x; }       }s[N];   int sta[N];     int get(int x) { return s[s[x].f].ch[1]==x; } int isr(int x) { return s[s[x].f].ch[0]!=x&&s[s[x].f].ch[1]!=x; }   void pushup(int x) {  s[x].mi=min(s[x].val,min(s[lson].mi,s[rson].mi));}    void mark(int x) {if(!x) return;   swap(lson,rson),s[x].rev^=1; }    void pushdown(int x) {if(s[x].rev) mark(lson),mark(rson),s[x].rev=0;  }     void rotate(int x) { int old=s[x].f,fold=s[old].f,which=get(x);  if(!isr(old)) s[fold].ch[s[fold].ch[1]==old]=x;     s[old].ch[which]=s[x].ch[which^1];   if(s[old].ch[which]) s[s[old].ch[which]].f=old;   s[x].ch[which^1]=old,s[old].f=x,s[x].f=fold;   pushup(old),pushup(x); }void splay(int x) {int u=x,v=0,fa;   for(sta[++v]=u;!isr(u);u=s[u].f)   sta[++v]=s[u].f;   for(;v;--v) pushdown(sta[v]);   for(u=s[u].f;(fa=s[x].f)!=u;rotate(x))       if(s[fa].f!=u)   rotate(get(fa)==get(x)?fa:x);     }int Access(int x) {  int y=0; for(;x;y=x,x=s[x].f)   splay(x),rson=y,pushup(x);     return y; }void makert(int x) {Access(x),splay(x),mark(x);  }void split(int x,int y) {makert(x),Access(y),splay(y);  }    void link(int x,int y) { s[x].f=y;     }  int get_lca(int x,int y) {    Access(x);      return Access(y); }
};    vector<int>G[N];
int val[N],dfn[N],low[N],S[N],tim,top,tot;
int hd[N],to[N],nex[N],edges,n,m,Q;
int fa[N];
multiset<int>mi[N];
void add(int u,int v)
{nex[++edges]=hd[u],hd[u]=edges,to[edges]=v;
}
void tarjan(int u)
{dfn[u]=low[u]=++tim; S[++top]=u;    for(int i=hd[u];i;i=nex[i]) {int v=to[i];    if(!dfn[v]) {tarjan(v),low[u]=min(low[u],low[v]);            if(low[v]>=dfn[u]) {       ++tot;   G[tot].push_back(u);    G[u].push_back(tot);  for(int x=0;x!=v;--top) {x=S[top];      G[tot].push_back(x); G[x].push_back(tot);      }}}else low[u]=min(low[u],dfn[v]);       }
}
void dfs(int x,int ff)
{     if(ff) lct::link(x,ff); if(x<=n) {    if(ff) mi[ff].insert(val[x]);      lct::s[x].val=lct::s[x].mi=val[x];    }for(int i=0;i<G[x].size();++i) {int y=G[x][i];   if(y!=ff) fa[y]=x,dfs(y,x);    }      if(x>n)  {lct::s[x].val=lct::s[x].mi=*mi[x].begin();  }
}
int main()
{   //setI("input");                    scanf("%d%d%d",&n,&m,&Q);    for(int i=1;i<=n;++i)   scanf("%d",&val[i]);     for(int i=1;i<=m;++i) {int x,y; scanf("%d%d",&x,&y); add(x,y),add(y,x);    }     tot=n;  for(int i=1;i<=n;++i)  if(!dfn[i])  tarjan(i);      dfs(1,0);      val[0]=inf;     for(int i=1;i<=Q;++i) {     char ch[2];   int x,b;  scanf("%s%d%d",ch,&x,&b);   if(ch[0]=='C')  {  lct::splay(x); lct::s[x].val=b;   lct::pushup(x);           if(fa[x]) {mi[fa[x]].erase(mi[fa[x]].lower_bound(val[x]));    mi[fa[x]].insert(b);    lct::splay(fa[x]);    lct::s[fa[x]].val=*mi[fa[x]].begin();         lct::pushup(fa[x]);   }              val[x]=b;    // modify(val[x] -> b)  } else {// query(a,b)      int lca=lct::get_lca(x,b);               if(lca<=n)  lca=0;   lct::split(x,b);     printf("%d\n",min(lct::s[b].mi,val[fa[lca]]));  lct::makert(1);         }     }                 return 0;
}