atcoder#ABC286D. [ABC286D] Money in Hand

[ABC286D] Money in Hand

Score : 400400 points

Problem Statement

Takahashi has NN kinds of coins; specifically, for 1iN1\leq i\leq N, he has BiB_i coins worth AiA_i yen (the currency in Japan) each.

Determine if Takahashi can pay exactly XX yen (without change) with the coins he currently has.

Constraints

  • 1N501\leq N\leq 50
  • 1X1041\leq X\leq 10^4
  • 1Ai1001\leq A_i\leq 100
  • 1Bi501\leq B_i\leq 50
  • AiA_i are pairwise distinct.
  • All values in the input are integers.

Input

The input is given from Standard Input in the following format:

NN XX

A1A_1 B1B_1

A2A_2 B2B_2

\vdots

ANA_N BNB_N

Output

Print Yes if Takahashi can pay exactly XX yen with the coins he currently has; print No otherwise.

2 19
2 3
5 6
Yes

Takahashi has three 22-yen coins and six 55-yen coins. He can use two 22-yen coins and three 55-yen coins to pay exactly 2×2+5×3=192\times 2+5\times 3=19 yen. Thus, Yes should be printed.

2 18
2 3
5 6
No

There is no combination of the coins that he can use to pay exactly 1818 yen. Thus, No should be printed.

3 1001
1 1
2 1
100 10
Yes

He need not use all kinds of coins.