package main

import (
	"fmt"
)

func main() {
	var n, s int
	fmt.Scan(&n, &s)

	maxSweets := -1

	for i := 0; i < n; i++ {
		var x, y int
		fmt.Scan(&x, &y)

		if x < s || (x == s && y == 0) {
			sweets := 0
			if y > 0 {
				sweets = 100 - y
			}
			if sweets > maxSweets {
				maxSweets = sweets
			}
		}
	}

	fmt.Println(maxSweets)
}