/*
1. 状态定义：f[j] 表示当体积恰好为j时的最大价值，g[j] 表示当体积恰好为j时的方案数
2. 状态计算：f[j] = MAX(f[j-v[i]])
            g[j] += f[j] == MAX ?  g[j]: 0
            g[j] += f[j-v[i]] == MAX ?  g[j-v[i]]: 0
3. 边界： f[0] = 0, f[~] = -INF
          g[0] = 1, g[~] = 0

*/

import java.util.*;

public class Main{

    void run(){
        int N = jin.nextInt();
        int V = jin.nextInt();
        for (int i = 1 ; i <= N ; i++){
            v[i] = jin.nextInt();
            w[i] = jin.nextInt();
        }

        Arrays.fill(f, Integer.MIN_VALUE);
        f[0] = 0;
        g[0] = 1;

        for (int i = 1 ; i <= N ; i++){
            for (int j = V ; j >= v[i] ;j--){
                int t = Math.max(f[j], f[j -v[i]] + w[i]); //忘记+w
                int s = 0;
                if (f[j] == t) s += g[j] %mod ;
                if (f[j-v[i]] + w[i]== t) s+= g[j-v[i]] %mod;  // 忘记+w
                f[j] = t;
                g[j] = s;
            }
        }


        int maxV = 0;
        int res = 0;
        for (int i = 1 ; i <= V ; i++) maxV = Math.max(maxV, f[i]);

        for (int i = 1 ; i <= V ; i++){
            if (f[i] == maxV) res += g[i] % mod;
        }

        System.out.println(res);
    }

    int mod = 1000000007;
    int maxN = 1002;
    int[] w = new int[maxN];
    int[] v = new int[maxN];
    int[] g = new int[maxN];
    int[] f = new int[maxN];
    Scanner jin = new Scanner (System.in);
    public static void main(String[] args) {new Main().run();}
}