#AT2448. D - Money in Hand

D - Money in Hand

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D - Money in Hand

Score : $400$ points

Problem Statement

Takahashi has $N$ kinds of coins; specifically, for $1\leq i\leq N$, he has $B_i$ coins worth $A_i$ yen (the currency in Japan) each.

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

Constraints

  • $1\leq N\leq 50$
  • $1\leq X\leq 10^4$
  • $1\leq A_i\leq 100$
  • $1\leq B_i\leq 50$
  • $A_i$ 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 $X$ yen with the coins he currently has; print No otherwise.


2 19
2 3
5 6
Yes

Takahashi has three $2$-yen coins and six $5$-yen coins. He can use two $2$-yen coins and three $5$-yen coins to pay exactly $2\times 2+5\times 3=19$ 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 $18$ yen. Thus, No should be printed.


3 1001
1 1
2 1
100 10
Yes

He need not use all kinds of coins.