Drazil is playing a math game with Varda.

Let's define <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> for positive integer *x* as a product of factorials of its digits. For example, <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/6784d861d9a724d0aeddefcb00b7d0c3442ae586.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

First, they choose a decimal number *a* consisting of *n* digits that contains at least one digit larger than 1. This number may possibly start with leading zeroes. Then they should find maximum positive number *x* satisfying following two conditions:

1. *x* doesn't contain neither digit 0 nor digit 1.

2. <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/7020b94c48be2ee5b8eeca05f379c8911bb0e7c4.png" style="max-width: 100.0%;max-height: 100.0%;"/> = <img align="middle" class="tex-formula" src="https://espresso.codeforces.com/aa57e017a6c74d06b0a54bc47e3f6990e5af38c1.png" style="max-width: 100.0%;max-height: 100.0%;"/>.

Help friends find such number.
The first line contains an integer *n* (1 ≤ *n* ≤ 15) — the number of digits in *a*.

The second line contains *n* digits of *a*. There is at least one digit in *a* that is larger than 1. Number *a* may possibly contain leading zeroes.
from collections import deque
import sys
dx=[1,-1,0,0]
dy=[0,0,1,-1]

def main():
    n,m=map(int,input().split())
    matrix=[]
    answer=[]
    degree=[]
    for i in range(n):
        l=list(input().replace(" ",""))
        matrix.append(l)
        answer.append(l)
        c=[0]*m
        degree.append(c)
    Solve(n,m,matrix,answer,degree)
    
    # matrix =[[for j in (input().split())] for i in range(n)]

def IsValid(x,y,n,m):
    return x>=0 and x<n and y>=0 and y<m

def Solve(n,m,matrix,answer,degree):
    q=deque()
    for i in range(n):    
        for j in range(m):
            if matrix[i][j]=='.':
                for k in range(4):
                    nx=i+dx[k]
                    ny=j+dy[k]
                    if IsValid(nx,ny,n,m) and matrix[nx][ny]=='.':
                        degree[i][j]+=1
    for i in range(n): 
        for j in range(m):
            if degree[i][j]==1 :
                q.append((i,j))
    while len(q)!=0:
        v=q.popleft()
        x=v[0]
        y=v[1]
        for k in range(4):
            nx=x+dx[k]
            ny=y+dy[k]
            if IsValid(nx,ny,n,m) and matrix[nx][ny]=='.': 
                if k==0:
                    answer[x][y]='^'
                    answer[nx][ny]='v'
                if k==1:
                    answer[x][y]='v'
                    answer[nx][ny]='^' 
                if k==2:
                    answer[x][y]='<'
                    answer[nx][ny]='>'
                if k==3:
                    answer[x][y]='>'
                    answer[nx][ny]='<'
                degree[x][y]=degree[nx][ny]=0
                for p in range(4):
                    nnx=nx+dx[p]
                    nny=ny+dy[p]
                    if IsValid(nnx,nny,n,m) and matrix[nnx][nny]=='.':
                        degree[nnx][nny]-=1
                        if degree[nnx][nny]==1:
                            q.append((nnx,nny))
    for i in range(n):
        for j in range(m):
            if answer[i][j]=='.':
                print("Not unique") 
                return
    a=""
    for i in range(n):
        # for j in range(m):
        #    a +=str(answer[i][j]+" ")
        print(''.join(answer[i]))
        # a=""
           


main()