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 C# (Mono 4.6.2.0) (judge verdict: Wrong Answer)

using System;
using System.Collections.Generic;
using System.Text;

namespace AtTest.ABC_104
{
    class C
    {
        static void Main(string[] args)
        {
            Method(args);
            Console.ReadLine();
        }

        static void Method(string[] args)
        {
            string[] input = Console.ReadLine().Split(' ');
            int d = int.Parse(input[0]);
            long g = int.Parse(input[1]);
            var scores = new List<long[]>();
            var cospa = new double[d];
            for (int i = 0; i < d; i++)
            {
                string[] inputs = Console.ReadLine().Split(' ');
                scores.Add(new long[int.Parse(inputs[0])]);
                for (int j = 0; j < scores[i].Length; j++)
                {
                    scores[i][j] = 100 * (i + 1) * (j + 1);
                }
                scores[i][scores[i].Length - 1] += long.Parse(inputs[1]);
                cospa[i] = scores[i][scores[i].Length - 1] / scores[i].Length;
            }

            var cospaIndex = new List<int>();
            for (int i = 0; i < d; i++)
            {
                for (int j = 0; j <= cospaIndex.Count; j++)
                {
                    if (j == cospaIndex.Count)
                    {
                        cospaIndex.Add(i);
                        break;
                    }
                    if (cospa[i] > cospa[cospaIndex[j]])
                    {
                        cospaIndex.Insert(0, i);
                        break;
                    }
                }
            }
            for(int i = 0; i < cospaIndex.Count; i++)
            {
                //Console.WriteLine(cospaIndex[i]);
            }

            int cnt = 0;
            while (g > 0)
            {
                for (int i = 0; i < 100; i++)//1数でどうにかなるとき
                {
                    for (int j = 0; j < scores.Count; j++)
                    {
                        if (i < scores[j].Length)
                        {
                            if (g <= scores[j][i])
                            {
                                cnt += i + 1;
                                Console.WriteLine(cnt);
                                return;
                            }
                        }
                    }
                }
                g -= scores[cospaIndex[0]][scores[cospaIndex[0]].Length - 1];
                cnt += scores[cospaIndex[0]].Length;
                scores.RemoveAt(cospaIndex[0]);
                for(int i = 0; i < cospaIndex.Count; i++)
                {
                    if (cospaIndex[i] > cospaIndex[0])
                    {
                        cospaIndex[i]--;
                    }
                }
                cospaIndex.RemoveAt(0);
            }

            Console.WriteLine(0);
        }
    }
}