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Time Limit: 2 sec / Memory Limit: 1024 MB

Score :

200

points

Problem Statement

There are

N

people. The family name and given name of the

i

-th person

\leq i \leq N)

are

S_i

and

T_i

, respectively.
Determine whether there is a pair of people with the same family and given names. In other words, determine whether there is a pair of integers

(i, j)

such that

\leq i \lt j \leq N

S_i=S_j

, and

T_i=T_j

Constraints

$\leq N \leq 1000$
$N$ is an integer.
Each of $S_i$ and $T_i$ is a string of length between $1$ and $10$ (inclusive) consisting of English lowercase letters.

Input

Input is given from Standard Input in the following format:

 $N$  $S_1$  $T_1$  $S_2$  $T_2$  $\hspace{0.6cm}\vdots$  $S_N$  $T_N$

Output

If there is a pair of people with the same family and given names, print Yes; otherwise, print No.

2238: Same Name

Description

Problem Statement

Constraints

Input

Output

Sample Input Copy

Sample Output Copy

Source/Category