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# coding: utf-8
# 自分の得意な言語で
# Let's チャレンジ！！
import re

input_line = input()
page_list = []
query_count = int(input_line)
empty = ''

for i in range(0,query_count):
    input_ = input()
    if re.match("^go to",input_) :
        page = re.match("(?:go to )(.{0,})$",input_)[1]
        empty = page
        page_list.append(page)
        
    else:
        page_list.pop()

    print(page_list[len(page_list) - 1])​

# coding: utf-8
# 自分の得意な言語で
# Let's チャレンジ！！
input_line = input()
input_list =input_line.split()
# print(input_list)
h = int(input_list[0])
w = int(input_list[1])
k = int(input_list[2])+1

list1 = list()

for i in range(0,h):
    row = list(input())
    list1.append(row)
    
# print(list1)
n = 'N'
nx = 0;
ny = 0;
for index, lst in enumerate(list1):
    if n in lst:
        nx = index
        ny = lst.index(str(n))
        
        
list_index = dict()
for i in range(1,k):
    for index, lst in enumerate(list1):
        if str(i) in lst:
            x = index
            y = lst.index(str(i))
            list_index[i] = [x,y]
            
            
            
# print(list_index)
        
        

output_list = list()
kake = 5000
for i in list(list_index):
    # print(list_index[i][0])
    x = list_index[i][0]
    y = list_index[i][1]
    
    sum1 = abs(nx-x) + abs(ny-y) 
    # print(sum1)
    if kake > sum1:
        kake = sum1
        output_list = list()
        output_list.append(i)
    elif kake == sum1:
        output_list.append(i)
    else:
        continue
    
output_list.sort()
print(len(output_list))
for i in output_list:
    print(i)