There is a farm whose length and width are A yard and B yard, respectively. A farmer, John, made a vertical road and a horizontal road inside the farm from one border to another, as shown below: (The gray part represents the roads.)

What is the area of this yard excluding the roads? Find it.

-----Note-----
It can be proved that the positions of the roads do not affect the area.

-----Constraints-----
 - A is an integer between 2 and 100 (inclusive).
 - B is an integer between 2 and 100 (inclusive).

-----Input-----
Input is given from Standard Input in the following format:
A B

-----Output-----
Print the area of this yard excluding the roads (in square yards).

-----Sample Input-----
2 2

-----Sample Output-----
1

In this case, the area is 1 square yard.

Difficulty: introductory

Starter code:

Solutions:
a,b=map(int, input().split())     
print(a*b-a-b+1)

n,m = map(int, input().split())
print((n-1)*(m-1))

a,b = list(map(int,input().split()))
print(((a-1) * (b-1)))


A, B = list(map(int, input().split()))
print(((A-1)*(B-1)))


a,b=map(int, input().split())

print((a-1)*(b-1))

a, b = map(int, input().split())
print((a * b) - (a + b - 1))

A,B = map(int,input().split())
print((A-1)*(B-1))

A, B = map(int, input().split())
print((A - 1) * (B - 1))

a,b = list(map(int,input().split()))
print(((a-1)*(b-1)))



A,B = map(int,input().split())
print(A*B-(A+B-1))

a,b=map(int,input().split())
print((a-1)*(b-1))

a, b = map(int, input().split())
print((a-1)*(b-1))

A, B = map(int, input().split())
ans = (A * B) - (A + B - 1)

print(ans)

a, b = map(int, input().split())
print((a - 1) * (b - 1))

A,B=list(map(int,input().split()))

print((A*B-A-B+1))


A,B = map(int, input().split())

print(A*B-A-B+1)

a, b = list(map(int, input().split()))
print(((a - 1) * (b - 1)))


A,B = list(map(int, input().split()))

ans = int(A*B-A-B+1)
print(ans)


a,b = map(int,input().split())
print((a-1)*(b-1))

A,B= (int(x) for x in input().split())
menseki=A*B
nyan=menseki-A-B+1
print(nyan)

A,B = (int(x) for x in input().split())
print((A-1)*(B-1))

import sys
import math

#https://atcoder.jp/contests/agc008/submissions/15248942
sys.setrecursionlimit(10 ** 8)
ini = lambda: int(sys.stdin.readline())
inm = lambda: map(int, sys.stdin.readline().split())
inl = lambda: list(inm())
ins = lambda: sys.stdin.readline().rstrip()
debug = lambda *a, **kw: print("\033[33m", *a, "\033[0m", **dict(file=sys.stderr, **kw))

A,B = inm()

print(A*B-A-B+1)


a,b = map(int,input().split())
print((a-1)*(b-1))

n,i=map(int,input().split())
print((n-1)*(i-1))

A,B=map(int,input().split())
print((A-1)*(B-1))

a,b = map(int, input().split())
print((a-1)*(b-1))

a,b = map(int,input().split())
print(a*b-a-b+1)

a, b = list(map(int, input().split()))
print((a-1)*(b-1))

a,b=map(int,input().split())
print((a-1)*(b-1))

a,b=map(int,input().split())
print((a-1)*(b-1))

a, b = map(int, input().split())
print((a-1)* (b-1))

a,b=map(int,input().split(" "))
print((a-1)*(b-1))

a, b = map(int, input().split())

print((a-1) * (b-1))

a,b = map(int,input().split())

print((a-1)*(b-1))

A,B = map(int,input().split())
print(A*B-A-B+1)

a,b = map(int, input().split())
print(a*b-a-b+1)

a, b = map(int, input().split())
print(a * b - a - b + 1)

A,B = map(int,input().split())
ans = A * B - (B + A - 1)
print(ans)

a,b = map(int,input().split())
print((a-1)*(b-1))

A, B = map(int, input().split())

print((A-1)*(B-1))

a, b = list(map(int, input().split()))
print((a*b - a - b + 1))


a,b = map(int,input().split())
print((a-1)*(b-1))

import sys
input = sys.stdin.readline
ins = lambda: input().rstrip()
ini = lambda: int(input().rstrip())
inm = lambda: map(int, input().split())
inl = lambda: list(map(int, input().split()))

a, b = inm()
print(a*b - 1*a - 1*b + 1)

a,b=input().split()
a=int(a)
b=int(b)
print(int((a-1)*(b-1)))

a, b = map(int, input().split())
print((a - 1) * (b - 1))

A, B = map(int, input().split())

print((A-1) * (B-1))

a,b = map(int,input().split())
print((a-1)*(b-1))

a,b=map(int, input().split())
print((a-1)*(b-1))

a,b= map(int,input().split())
print((a-1)*(b-1))


a,b=map(int,input().split())
print((a-1)*(b-1))

a,b=map(int,input().split())
print((a-1)*(b-1))

A,B=list(map(int,input().split()))
print((A*B-(A+B-1)))



w,h = map(int, input().split(" "))
print((w-1)*(h-1))

a,b,=map(int,input().split())
print((a-1)*(b-1))

a,b=map(int, input().split())
print(a*b-a-b+1)

a,b = [int(x) for x in input().split()]
print((a-1)*(b-1))

A, B = list(map(int, input().split()))
print(((A-1)*(B-1)))


a,b = map(int,input().split())
print((a-1)*(b-1))

a,b = map(int, input().split())
print((a-1)*(b-1))

a, b = map(int, input().split())
print(a*b-(a+b-1))

A,B=list(map(int,input().split()))
print(((A-1)*(B-1)))


a,b=map(int,input().split())
print((a-1)*(b-1))

a, b = map(int, input().split())
print((a-1)*(b-1))

A,B=map(int,input().split())
print((A-1)*(B-1))

import sys

read = sys.stdin.read
readline = sys.stdin.readline
readlines = sys.stdin.readlines
sys.setrecursionlimit(10 ** 9)
INF = 1 << 60
MOD = 1000000007


def main():
    A, B = list(map(int, readline().split()))

    print(((A - 1) * (B - 1)))

    return


def __starting_point():
    main()

__starting_point()

len_a, len_b = list(map(int, input().split()))

total_area = len_a * len_b
road = len_a + len_b - 1
print((total_area - road))


A, B = map(int, input().split())
print((A*B) - (A + B - 1))

a,b=map(int,input().split())
print((a-1)*(b-1))

a, b = map(int, input().split())
print(a*b - (a+b-1))

a,b=map(int,input().split())
print((a-1)*(b-1))

#!/usr/bin/env python3

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


def __starting_point():
    main()

__starting_point()

A, B,  = map(int, input().split())
print((A-1)*(B-1))

a, b = map(int, input().split())
print((a-1)*(b-1))

A, B = map(int, input().split())
print(A*B-A-B+1)

a,b = map(int,input().split())
print((a-1)*(b-1))

a, b = map(int, input().split())
print((a - 1) * (b - 1))

A, B = map(int, input().split())

C = A - 1
D = B - 1
E = C * D

print(E)

a, b = map(int, input().split())
ans = (a-1) * (b-1)
print(ans)

def mapt(fn, *args):
    return list(map(fn, *args))


def Input():
    return mapt(int, input().split(" "))


def main():
    a, b = Input()
    print((a-1) * (b-1))


main()

# ABC106
# A Garden
A, B = list(map(int, input().split()))
ans = (A * B) - (A + B - 1)
print(ans)


A,B = map(int, input().split())
print(A*B-(A+B-1))

a,b = map(int,input().split())
print((a-1)*(b-1))

H, W = map(int, input().split())

print((H-1)*(W-1))

a,b = map(int, input ().split ())
print ((a-1)*(b-1))

a,b = map(int,input().split())
print(a*b-a-b+1)

a, b = map(int, input().split())

print((a - 1) * (b - 1))

a,b=map(int,input().split())
print((a-1)*(b-1))

a,b=map(int,input().split())
print(a*b-b-a+1)

a,b = map(int,input().split())
print(str(a*b-a-b+1))

A, B = map(int, input().split())
print((A-1) * (B - 1))

a, b = map(int, input().split())
res = (a - 1) * (b - 1)
print(res)

a, b = map(int, input().split())
print((a-1)*(b-1))

a,b=map(int,input().split())
ans=(a-1)*(b-1)
print(ans)

a, b = map(int, input().split())
print(a * b - a - b + 1)

x, y = map(int, input().split())
print(x*y - x - y + 1)

a,b=map(int,input().split())
print(int((a-1)*(b-1)))

a, b = map(int, input().split())
print((a*b) - (a + b - 1))

a, b = map(int, input().split())

print((a - 1) * (b - 1))

# coding = SJIS

a, b = map(int, input().split())

print((a - 1) * (b - 1))

a,b,=map(int,input().split())
a-=1;b-=1
print(a*b)