Problem: Given are integers A, B, and N.  Find the maximum possible value of floor(Ax/B) - A × floor(x/B) for a non- negative integer x not greater than N.  Here floor(t) denotes the greatest integer not greater than the real number t.

Submission attempts (in order):
import sys, bisect, math, itertools, string, queue, copy
# import numpy as np

from collections import Counter,defaultdict,deque
from itertools import permutations, combinations
from heapq import heappop, heappush
from fractions import gcd
# input = sys.stdin.readline
sys.setrecursionlimit(10**8)
mod = 10**9+7
def inp(): return int(input())
def inpm(): return map(int,input().split())
def inpl(): return list(map(int, input().split()))
def inpls(): return list(input().split())
def inplm(n): return list(int(input()) for _ in range(n))
def inplL(n): return [list(input()) for _ in range(n)]
def inplT(n): return [tuple(input()) for _ in range(n)]
def inpll(n): return [list(map(int, input().split())) for _ in range(n)]
def inplls(n): return sorted([list(map(int, input().split())) for _ in range(n)])

def main():
    a,b,n = inpm()
    print(max(int(a*(b-1)/b),int(a*n/b)))

if __name__ == "__main__":
    main()

import sys, bisect, math, itertools, string, queue, copy
# import numpy as np

from collections import Counter,defaultdict,deque
from itertools import permutations, combinations
from heapq import heappop, heappush
from fractions import gcd
# input = sys.stdin.readline
sys.setrecursionlimit(10**8)
mod = 10**9+7
def inp(): return int(input())
def inpm(): return map(int,input().split())
def inpl(): return list(map(int, input().split()))
def inpls(): return list(input().split())
def inplm(n): return list(int(input()) for _ in range(n))
def inplL(n): return [list(input()) for _ in range(n)]
def inplT(n): return [tuple(input()) for _ in range(n)]
def inpll(n): return [list(map(int, input().split())) for _ in range(n)]
def inplls(n): return sorted([list(map(int, input().split())) for _ in range(n)])

def main():
    a,b,n = inpm()
    ans = 0
    for i in range(min(b+1,n+1)):
        ans = max(ans,int(a*i/b)-a*int(i/b))
    print(ans)

if __name__ == "__main__":
    main()

import sys, bisect, math, itertools, string, queue, copy
# import numpy as np

from collections import Counter,defaultdict,deque
from itertools import permutations, combinations
from heapq import heappop, heappush
from fractions import gcd
# input = sys.stdin.readline
sys.setrecursionlimit(10**8)
mod = 10**9+7
def inp(): return int(input())
def inpm(): return map(int,input().split())
def inpl(): return list(map(int, input().split()))
def inpls(): return list(input().split())
def inplm(n): return list(int(input()) for _ in range(n))
def inplL(n): return [list(input()) for _ in range(n)]
def inplT(n): return [tuple(input()) for _ in range(n)]
def inpll(n): return [list(map(int, input().split())) for _ in range(n)]
def inplls(n): return sorted([list(map(int, input().split())) for _ in range(n)])

def main():
    a,b,n = inpm()
    ans = 0
    for i in range(min(10**6+10,n+1)):
        ans = max(ans,int(a*i/b)-a*int(i/b))
    print(ans)

if __name__ == "__main__":
    main()

def main():
    a,b,n = map(int,input().split())
    print(int(a*min((b-1),n)/b) - a*int(min((b-1),n)/b))

if __name__ == "__main__":
    main()

Verdicts: Wrong Answer

Time Limit Exceeded

Wrong Answer

Accepted