#!/usr/bin/env python3

import collections
import sys

# Constants

INFINITY = float('inf')

# Turtle Tuple

Turtle = collections.namedtuple('Turtle', 'weight strength capacity')

# Compute Weights

def compute_weights(turtles):
    # TODO: 1. Insert sentinel/padding into list of turtles
    table = [[INFINITY for i in range(len(turtles)+1)] for j in range(len(turtles)+1)]
    n = len(turtles)
    # TODO: 2. Initialize weights table:
    #
    #   Weights(i, j) = Minimum weight of selecting j turtles from first i turtles
    #
    # By default, we set Weights(i, j) to INFINITY

    # If we can select no turtles (j == 0), then minimum weight is 0

    # TODO: 3. Construct table to minimize weight of selecting j turtles from
    # the first i turtles:
    #
    #   If Turtle(i)'s capacity >= Weights(i - 1, j - 1) Then
    #       Weights(i, j) = Min(Weights(i - 1, j),
    #                           Weights(i - 1, j - 1) + Turtles[i].weight)
    #   Otherwise
    #       Weights(i, j) = Weights(i - 1, j)
    for i in range(n):
        for j in range(n):
           if j == 0:
              table[i][j] = 0
              continue
           if turtles[i].capacity >= table[i-1][j-1]:
              table[i][j] = min(table[i-1][j], table[i-1][j-1] + turtles[i].weight)
           else:
              table[i][j] = table[i-1][j]
    # TODO: 4. Return table of weight
    return table
# Count turtles

def determine_count(Turtles, Weights):
    # TODO: Determine number of turtles in stack
    count = 0
    bottom_row = len(Turtles) - 1
    for turtle in Weights[bottom_row]:
        if turtle != INFINITY:
           count += 1
    return count
# Main execution

if __name__ == '__main__':
    Numbers = map(lambda line: list(map(int, line.split())), sys.stdin)
    Turtles = map(lambda args: Turtle(args[0], args[1], args[1] - args[0]), Numbers)
    Turtles = sorted(Turtles, key=lambda x: x.capacity)# TODO: Sort turtles by capacity
    Weights = compute_weights(Turtles)
    Count   = determine_count(Turtles, Weights)
    print(Count)