A. Double Click
import sys
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
n, d = list(map(int, input().rstrip('\n').split()))
t = list(map(int, input().rstrip('\n').split()))
for i in range(1, n):
if t[i] - t[i-1] <= d:
print(t[i])
exit()
print(-1)
if __name__ == '__main__':
solve()
B. chess960
import sys
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
s = str(input().rstrip('\n'))
if s.index("B") % 2 == s.rindex("B") % 2:
print("No")
else:
if s.index("R") < s.index("K") < s.rindex("R"):
print("Yes")
else:
print("No")
if __name__ == '__main__':
solve()
C. PC on the Table
import sys
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
h, w = list(map(int, input().rstrip('\n').split()))
s = [list(str(input().rstrip('\n'))) for _ in range(h)]
for i in range(h):
for j in range(w):
if s[i][j] == "T" and j < w - 1 and s[i][j + 1] == "T":
s[i][j] = "P"
s[i][j + 1] = "C"
for i in range(h):
print("".join(s[i]))
if __name__ == '__main__':
solve()
D. Count Subtractions
import sys
def solve():
input = sys.stdin.readline
mod = 10 ** 9 + 7
a, b = list(map(int, input().rstrip('\n').split()))
ans = 0
while a != 1 and b != 1 and a != b:
if a > b:
dv, md = divmod(a, b)
ans += dv if md != 0 else dv - 1
a = md if md != 0 else b
else:
dv, md = divmod(b, a)
ans += dv if md != 0 else dv - 1
b = md if md != 0 else a
print(ans + abs(a - b))
if __name__ == '__main__':
solve()