Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    from scipy.optimize import dual_annealing
    A = [a-i for i, a in enumerate(A, 1)]
    def f(b):
        return sum(abs(a-b) for a in A)
    res = dual_annealing(f, [[min(A), max(A)+1]], maxiter=100)
    #print(res)
    b = res.x[0]
    return min(f(int(round(b))), f(int(round(b+1))))

# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"    
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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


Fixed submission:
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    A = sorted(a - i for i, a in enumerate(A))
    m = A[N//2]
    return sum(abs(a-m) for a in A)


# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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

Buggy python submission (verdict: Runtime Error):
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    from scipy.optimize import dual_annealing
    A = [a-i for i, a in enumerate(A, 1)]
    def f(b):
        return sum(abs(a-b) for a in A)
    res = dual_annealing(f, [[min(A), max(A)]], maxiter=500)
    # print(res)
    b = res.x[0]
    return min(f(int(round(b))), f(int(round(b+1))))

# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"    
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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


Fixed submission:
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    A = sorted(a - i for i, a in enumerate(A))
    m = A[N//2]
    return sum(abs(a-m) for a in A)


# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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

Buggy python submission (verdict: Runtime Error):
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    from scipy.optimize import dual_annealing
    A = [a-i for i, a in enumerate(A, 1)]
    def f(b):
        return sum(abs(a-b) for a in A)
    res = dual_annealing(f, [[min(A), max(A)]], maxiter=1000)
    # print(res)
    b = res.x[0]
    return min(f(int(round(b))), f(int(round(b+1))))

# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"    
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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


Fixed submission:
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    A = sorted(a - i for i, a in enumerate(A))
    m = A[N//2]
    return sum(abs(a-m) for a in A)


# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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

Buggy python submission (verdict: Time Limit Exceeded):
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    from scipy.optimize import rosen, differential_evolution, minimize, basinhopping
    A = [a-i for i, a in enumerate(A, 1)]
    def f(b):
        return sum(abs(a-b) for a in A)
    res = differential_evolution(f, [[min(A), max(A)]])
    b = res.x[0]
    return min(f(int(round(b))), f(int(round(b+1))))

# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"    
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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


Fixed submission:
#!/usr/bin/env python3
import sys

def solve(N: int, A: "List[int]"):
    A = sorted(a - i for i, a in enumerate(A))
    m = A[N//2]
    return sum(abs(a-m) for a in A)


# Generated by 1.1.7.1 https://github.com/kyuridenamida/atcoder-tools
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    N = int(next(tokens))  # type: int
    A = [int(next(tokens)) for _ in range(N)]  # type: "List[int]"
    print(solve(N, A))

def test():
    import doctest
    doctest.testmod()

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