There are $N$ people. The family name and given name of the $i$\-th person $(1 \leq i \leq N)$ 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 $1 \leq i \lt j \leq N$, $S_i=S_j$, and $T_i=T_j$.
输入格式
Input is given from Standard Input in the following format:
>$N$\
>$S_1$ $T_1$\
>$S_2$ $T_2$\
>$\hspace{0.6cm}\vdots$\
>$S_N$ $T_N$
#### Constraints
- $2 \leq N \leq 1000$
- $N$ 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.
输出格式
If there is a pair of people with the same family and given names, print `Yes`; otherwise, print `No`.