1 //140MS    6012K    2970 B    C++
  2 #include<stdio.h>
  3 #define NH 105
  4 #define NA 1005
  5 struct sub_node{
  6     int l;
  7     int r;
  8     int max;
  9 };
 10 struct node{
 11     sub_node st[4*NA];
 12     int l;
 13     int r; 
 14 }tree[4*NH];
 15 inline int Max(int a,int b)
 16 {
 17     return a>b?a:b;
 18 }
 19 void sub_build(int l,int r,int rt,int prt)
 20 {
 21     tree[prt].st[rt].l=l;
 22     tree[prt].st[rt].r=r;
 23     tree[prt].st[rt].max=-1;
 24     if(l==r) return;
 25     int mid=(l+r)>>1;
 26     sub_build(l,mid,2*rt,prt);
 27     sub_build(mid+1,r,2*rt+1,prt);
 28 }
 29 void build(int l,int r,int prt,int sl,int sr)
 30 {
 31     tree[prt].l=l;
 32     tree[prt].r=r;
 33     sub_build(sl,sr,1,prt);
 34     if(l==r) return;
 35     int mid=(l+r)>>1;
 36     build(l,mid,2*prt,sl,sr);
 37     build(mid+1,r,2*prt+1,sl,sr);
 38 }
 39 void sub_update(int A,int L,int rt,int prt)
 40 {
 41     if(tree[prt].st[rt].l==tree[prt].st[rt].r){
 42         tree[prt].st[rt].max=Max(tree[prt].st[rt].max,L);
 43         return;
 44     }
 45     int mid=(tree[prt].st[rt].l+tree[prt].st[rt].r)>>1;
 46     if(A<=mid) sub_update(A,L,2*rt,prt);
 47     else sub_update(A,L,2*rt+1,prt);
 48     tree[prt].st[rt].max=Max(tree[prt].st[2*rt].max,tree[prt].st[2*rt+1].max);
 49 }
 50 void update(int H,int A,int L,int prt)
 51 {
 52     sub_update(A,L,1,prt);
 53     if(tree[prt].l==tree[prt].r) return;
 54     int mid=(tree[prt].l+tree[prt].r)>>1;
 55     if(H<=mid) update(H,A,L,2*prt);
 56     else update(H,A,L,2*prt+1);
 57 }
 58 int sub_query(int A1,int A2,int rt,int prt)
 59 {
 60     if(A1<=tree[prt].st[rt].l && A2>=tree[prt].st[rt].r)
 61         return tree[prt].st[rt].max;
 62     if(A2<=tree[prt].st[2*rt].r) return sub_query(A1,A2,2*rt,prt);
 63     else if(A1>=tree[prt].st[2*rt+1].l) return sub_query(A1,A2,2*rt+1,prt);
 64     else return Max(sub_query(A1,tree[prt].st[2*rt].r,2*rt,prt),sub_query(tree[prt].st[2*rt+1].l,A2,2*rt+1,prt));
 65 }
 66 int query(int H1,int H2,int A1,int A2,int prt)
 67 {
 68     if(H1<=tree[prt].l && H2>=tree[prt].r){
 69         return sub_query(A1,A2,1,prt);
 70     }
 71     if(H2<=tree[2*prt].r) return query(H1,H2,A1,A2,2*prt);
 72     else if(H1>=tree[2*prt+1].l) return query(H1,H2,A1,A2,2*prt+1);
 73     else{
 74         return Max(query(H1,tree[2*prt].r,A1,A2,2*prt),query(tree[2*prt+1].l,H2,A1,A2,2*prt+1));
 75     }
 76 }
 77 int main(void)
 78 {
 79     int n,H1,H2;
 80     double A1,A2,L;
 81     char op;
 82     while(scanf("%d%*c",&n),n)
 83     {
 84         build(0,100,1,0,1000);
 85         while(n--){
 86             scanf("%c",&op);
 87             if(op==‘I‘){
 88                 scanf("%d%lf%lf%*c",&H1,&A1,&L);
 89                 update(H1-100,(int)(A1*10),(int)(L*10),1);
 90             }else{
 91                 scanf("%d%d%lf%lf%*c",&H1,&H2,&A1,&A2);
 92                 if(H1>H2){
 93                     int temp=H1;H1=H2;H2=temp;
 94                 }
 95                 if(A1>A2){
 96                     double temp=A1;A1=A2;A2=temp;
 97                 }
 98                 int ans=query(H1-100,H2-100,(int)(A1*10),(int)(A2*10),1);
 99                 if(ans==-1) puts("-1");
100                 else printf("%.1lf\n",ans/10.0);
101             } 
102         }
103     }
104     return 0;
105 }