A. Probably English
import sys
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
d = {"and", "not", "that", "the", "you"}
n = int(input().rstrip('\n'))
w = list(map(str, str(input().rstrip('\n')).split()))
for i in range(n):
if w[i] in d:
print("Yes")
exit()
print("No")
if __name__ == '__main__':
solve()
B. Bombs
import sys
import collections
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
r, c = list(map(int, input().rstrip('\n').split()))
b = [list(str(input().rstrip('\n'))) for _ in range(r)]
st = []
for i in range(r):
for j in range(c):
if b[i][j] != "." and b[i][j] != "#":
st.append([i, j, int(b[i][j])])
for i, j, d in st:
ql = [[0, i, j]]
ql = collections.deque(ql)
fq = collections.defaultdict(list)
fq[i, j]
while True:
if len(ql) != 0:
cost, xv, yv = ql.popleft()
if cost <= d:
b[xv][yv] = "."
for xv, yv in [[xv + 1, yv], [xv - 1, yv], [xv, yv + 1], [xv, yv - 1]]:
if 0 <= xv < r and 0 <= yv < c:
if (xv, yv) not in fq:
ql.append([cost + 1, xv, yv])
fq[xv, yv]
else:
break
for i in range(r):
print("".join(b[i]))
if __name__ == '__main__':
solve()
C. Socks
import sys
import collections
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
n = int(input().rstrip('\n'))
a = collections.Counter(list(map(int, input().rstrip('\n').split())))
ans = 0
for k, v in a.items():
ans += v // 2
print(ans)
if __name__ == '__main__':
solve()
D. Three Days Ago
import sys
import collections
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
s = str(input().rstrip('\n'))
dp = [[0] * 10 for _ in range(len(s) + 1)]
d = collections.defaultdict(list)
d[0] += [0]
for i in range(len(s) + 1):
if i > 0:
dp[i][int(s[i-1])] += 1
b = 0
for j in range(10):
dp[i][j] += dp[i-1][j]
dp[i][j] %= 2
if dp[i][j] == 1:
b += pow(10, j)
d[b] += [i]
ans = 0
for k, v in d.items():
ans += sum([i for i in range(len(v))])
print(ans)
if __name__ == '__main__':
solve()