我第3名,我的同學第4名,我的老師第2名.....

import sys

input = sys.stdin.read
data = input().split()

idx = 0
N = int(data[idx])
M = int(data[idx + 1])
idx += 2

C = data[idx]
idx += 1

S = []
for i in range(N):
    S.append(int(data[idx]))
    idx += 1

for i in range(N):
    si = S[i]

    row = []
    for j in range(M - 1, -1, -1):  
        if (si & (1 << j)) != 0:
            row.append(C)
        else:
            row.append('.')
    print(' '.join(row))