Warehouse Bin Number Locator

A warehouse control system stores a number in each indexed bin. Starting with all bins empty, it processes q operations, each one of:

• SET index number — place number into bin index, replacing whatever was there.
• FIND number — report the smallest bin index currently holding number, or -1 if no bin currently holds it.

Input format

Line 1: an integer q. Next q lines: SET index number or FIND number.

Output format

For each FIND operation, in order, print the smallest matching index, or -1.

Constraints

• 1 <= q <= 40
• 1 <= index <= 1000000
• 1 <= number <= 1000000