Problem:
Range Minimum Query (RMQ)

Write a program which manipulates a sequence A = {a0, a1, . . . , an-1} with the following operations:

find(s, t): report the minimum element in as, as+1, . . . ,at.

update(i, x): change ai to x.

Note that the initial values of ai (i = 0, 1, . . . , n−1) are 231-1.

Input

n q
com0 x0 y0
com1 x1 y1
...
comq−1 xq−1 yq−1

In the first line, n (the number of elements in A) and q (the number of queries) are given. Then, q queries are given where com represents the type of queries. '0' denotes update(xi, yi) and '1' denotes find(xi, yi).

Output

For each find operation, print the minimum element.

Constraints

1 ≤ n ≤ 100000

1 ≤ q ≤ 100000

If comi is 0, then 0 ≤ xi < n, 0 ≤ yi < 231-1.

If comi is 1, then 0 ≤ xi < n, 0 ≤ yi < n.

Sample Input 1

3 5
0 0 1
0 1 2
0 2 3
1 0 2
1 1 2

Sample Output 1

1
2

Sample Input 2

1 3
1 0 0
0 0 5
1 0 0

Sample Output 2

2147483647
5

Solution in Scala (judge verdict: Wrong Answer)

object Main extends App {
    val in = io.Source.stdin.getLines.map(_.split(" ").map(_.toInt))
    in.next
    in.foldLeft(List[Array[Int]]())((qs, q) => q match {
        case Array(0, _*) => q.tail +: qs
        case Array(1, s, t) => {
            var x = qs
            var y = (s to t).toSet
            var res = 2147483647
            while (x.nonEmpty && y.nonEmpty) {
                y = y - x.head(0)
                res = res min x.head(1)
                x = x.tail
            }
            println(res)
            qs
        }
    })
}