Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0,flush = True)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid, flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0,flush = True)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid, flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid,flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0,flush = True)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid, flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid,flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0,flush = True)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid, flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid,flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                s = x

    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0,flush = True)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid, flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid,flush = True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid

    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0,flush = True)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid, flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid

    return


#main
if __name__ == '__main__':
    solve()


Fixed submission:
#!/usr/bin/env python3
from collections import defaultdict,deque
from heapq import heappush, heappop
from bisect import bisect_left, bisect_right
import sys, random, itertools, math
sys.setrecursionlimit(10**5)
input = sys.stdin.readline
sqrt = math.sqrt
def LI(): return list(map(int, input().split()))
def LF(): return list(map(float, input().split()))
def LI_(): return list(map(lambda x: int(x)-1, input().split()))
def II(): return int(input())
def IF(): return float(input())
def S(): return input().rstrip()
def LS(): return S().split()
def IR(n): return [II() for _ in range(n)]
def LIR(n): return [LI() for _ in range(n)]
def FR(n): return [IF() for _ in range(n)]
def LFR(n): return [LI() for _ in range(n)]
def LIR_(n): return [LI_() for _ in range(n)]
def SR(n): return [S() for _ in range(n)]
def LSR(n): return [LS() for _ in range(n)]
mod = 1000000007
inf = 1e10

#solve
def solve():
    n = II()
    print(0,flush = True)
    s = S()
    if s == "Vacant":
        return
    x = s
    ok = 0
    ng = n
    while 1:
        mid = (ok + ng) // 2
        print(mid, flush=True)
        s = S()
        if s == "Vacant":
            return
        if mid & 1 == ok & 1:
            if s == x:
                ok = mid
            else:
                ng = mid
        else:
            if s == x:
                ng = mid
            else:
                ok = mid
                x = s

    return


#main
if __name__ == '__main__':
    solve()