Problem:
Score : 300 points

Problem Statement

A programming competition site AtCode provides algorithmic problems.
Each problem is allocated a score based on its difficulty.
Currently, for each integer i between 1 and D (inclusive), there are p_i problems with a score of 100i points.
These p_1 + … + p_D problems are all of the problems available on AtCode.

A user of AtCode has a value called total score.
The total score of a user is the sum of the following two elements:

Base score: the sum of the scores of all problems solved by the user.

Perfect bonuses: when a user solves all problems with a score of 100i points, he/she earns the perfect bonus of c_i points, aside from the base score (1 ≤ i ≤ D).

Takahashi, who is the new user of AtCode, has not solved any problem.
His objective is to have a total score of G or more points.
At least how many problems does he need to solve for this objective?

Constraints

1 ≤ D ≤ 10

1 ≤ p_i ≤ 100

100 ≤ c_i ≤ 10^6

100 ≤ G

All values in input are integers.

c_i and G are all multiples of 100.

It is possible to have a total score of G or more points.

Input

Input is given from Standard Input in the following format:

D G
p_1 c_1
:
p_D c_D

Output

Print the minimum number of problems that needs to be solved in order to have a total score of G or more points. Note that this objective is always achievable (see Constraints).

Sample Input 1

2 700
3 500
5 800

Sample Output 1

3

In this case, there are three problems each with 100 points and five problems each with 200 points. The perfect bonus for solving all the 100-point problems is 500 points, and the perfect bonus for solving all the 200-point problems is 800 points. Takahashi's objective is to have a total score of 700 points or more.

One way to achieve this objective is to solve four 200-point problems and earn a base score of 800 points. However, if we solve three 100-point problems, we can earn the perfect bonus of 500 points in addition to the base score of 300 points, for a total score of 800 points, and we can achieve the objective with fewer problems.

Sample Input 2

2 2000
3 500
5 800

Sample Output 2

7

This case is similar to Sample Input 1, but the Takahashi's objective this time is 2000 points or more. In this case, we inevitably need to solve all five 200-point problems, and by solving two 100-point problems additionally we have the total score of 2000 points.

Sample Input 3

2 400
3 500
5 800

Sample Output 3

2

This case is again similar to Sample Input 1, but the Takahashi's objective this time is 400 points or more. In this case, we only need to solve two 200-point problems to achieve the objective.

Sample Input 4

5 25000
20 1000
40 1000
50 1000
30 1000
1 1000

Sample Output 4

66

There is only one 500-point problem, but the perfect bonus can be earned even in such a case.

Solution in Go (1.6) (judge verdict: Time Limit Exceeded)

//  ABC104_C_AllGreen.go
// 

package main

import (
    "fmt"
    //"strings"
)

var pc [][]int
var pointMatrix [][]int
var rpointMatrix [][]int
var min int

func calPoint(point int,i int ,D int ,G int,correct int,min *int) {

  if i == D - 1 {
      for j := 0; j < len(rpointMatrix[i]); j++{
          //fmt.Println(j,":",point+pointMatrix[i][j],"correct:",correct+j)
          if point+rpointMatrix[i][j] >= G && correct+j <= *min {
             *min = correct+j
          }
      }
      return

  } else {

     for j := 0 ; j < len(rpointMatrix[i]) ; j++ {
       //fmt.Print(j,"-")
        if correct+j >= *min {
           break
        }

        if point+rpointMatrix[i][j] >= G && correct+j <= *min {
          *min = correct + j
          break
        }
        calPoint(point+rpointMatrix[i][j],i+1,D,G,correct+j,min)
     }
  }
}

func main() {
  var D int
  var G int
  var P int
  var C int
  var point int
  var correct int

  fmt.Scan(&D,&G)

  pc = make([][]int,D)

  for i := 0; i < D; i++ {
     pc[i] = make([]int,2)
  }

  min = 1

  for i := 0 ; i < D ; i++ {
    fmt.Scan(&P,&C)
    pc[i][0] = P
    pc[i][1] = C
    min *= P

    }

  //fmt.Println(pc)

  pointMatrix = make([][]int,D)

  for i := 0; i < D; i++ {
    pointMatrix[i] = make([]int,pc[i][0]+1)
  }

  for i :=0; i < D; i++ {
    for j :=0 ; j <= pc[i][0]; j++ {
      pointMatrix[i][j] = j * (i+1) * 100
    }
      pointMatrix[i][pc[i][0]] += pc[i][1]
   }

  rpointMatrix = make([][]int,D)

  for i := 0; i < D; i++ {
    rpointMatrix[i] = make([] int,pc[D-1-i][0]+1)
    rpointMatrix[i] = pointMatrix[D-1-i]
  }



  //fmt.Println(pointMatrix)
  //fmt.Println(rpointMatrix)

  point = 0
  correct = 0

  calPoint(point,0,D,G,correct,&min)

  //fmt.Println(point,correct,min)
  fmt.Println(min)
}