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


def solve(H: int, N: int, A: "List[int]", B: "List[int]"):
    mp = [0] * (H + 1)
    for i in range(1, len(mp)):
        ml = [0 for j in range(N)]
        for j in range(N):
            if i - A[j] < 0:
                ml[j] = mp[0] + B[j]
            else:
                ml[j] = mp[i - A[j]] + B[j]
        mp[i] = min(ml)
    print(mp[-1])   


# Generated by 1.1.6 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    H = int(next(tokens))  # type: int
    N = int(next(tokens))  # type: int
    A = [int()] * (N)  # type: "List[int]"
    B = [int()] * (N)  # type: "List[int]"
    for i in range(N):
        A[i] = int(next(tokens))
        B[i] = int(next(tokens))
    solve(H, N, A, B)

if __name__ == '__main__':
    main()


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


def solve(H: int, N: int, A: "List[int]", B: "List[int]"):
    mp = [0] * (H + 1)
    for i in range(1, len(mp)):
        ml = [0 for j in range(N)]
        for j in range(N):
            if i - A[j] < 0:
                ml[j] = mp[0] + B[j]
            else:
                ml[j] = mp[i - A[j]] + B[j]
        mp[i] = min(ml)
    print(mp[-1])   


# Generated by 1.1.6 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    H = int(next(tokens))  # type: int
    N = int(next(tokens))  # type: int
    A = [int()] * (N)  # type: "List[int]"
    B = [int()] * (N)  # type: "List[int]"
    for i in range(N):
        A[i] = int(next(tokens))
        B[i] = int(next(tokens))
    solve(H, N, A, B)

if __name__ == '__main__':
    main()

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


def solve(H: int, N: int, A: "List[int]", B: "List[int]"):
    mp = [0] * (H + 1)
    for i in range(1, len(mp)):
        ml = []
        for j in range(N):
            if i - A[j] < 0:
                ml.append(mp[0] + B[j])
            else:
                ml.append(mp[i - A[j]] + B[j])
        mp[i] = min(ml)
    print(mp[-1])   


# Generated by 1.1.6 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    H = int(next(tokens))  # type: int
    N = int(next(tokens))  # type: int
    A = [int()] * (N)  # type: "List[int]"
    B = [int()] * (N)  # type: "List[int]"
    for i in range(N):
        A[i] = int(next(tokens))
        B[i] = int(next(tokens))
    solve(H, N, A, B)

if __name__ == '__main__':
    main()


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


def solve(H: int, N: int, A: "List[int]", B: "List[int]"):
    mp = [0] * (H + 1)
    for i in range(1, len(mp)):
        ml = [0 for j in range(N)]
        for j in range(N):
            if i - A[j] < 0:
                ml[j] = mp[0] + B[j]
            else:
                ml[j] = mp[i - A[j]] + B[j]
        mp[i] = min(ml)
    print(mp[-1])   


# Generated by 1.1.6 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    H = int(next(tokens))  # type: int
    N = int(next(tokens))  # type: int
    A = [int()] * (N)  # type: "List[int]"
    B = [int()] * (N)  # type: "List[int]"
    for i in range(N):
        A[i] = int(next(tokens))
        B[i] = int(next(tokens))
    solve(H, N, A, B)

if __name__ == '__main__':
    main()

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


def solve(H: int, N: int, A: "List[int]", B: "List[int]"):
    mp = [0] * (H + 1)
    for i in range(1, len(mp)):
        m = 10 ** 9
        for j in range(N):
            if i - A[j] < 0:
                m = min(m, mp[0] + B[j])
            else:
                m = min(m, mp[i - A[j]] + B[j])
        mp[i] = m
    print(mp[-1])   


# Generated by 1.1.6 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    H = int(next(tokens))  # type: int
    N = int(next(tokens))  # type: int
    A = [int()] * (N)  # type: "List[int]"
    B = [int()] * (N)  # type: "List[int]"
    for i in range(N):
        A[i] = int(next(tokens))
        B[i] = int(next(tokens))
    solve(H, N, A, B)

if __name__ == '__main__':
    main()


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


def solve(H: int, N: int, A: "List[int]", B: "List[int]"):
    mp = [0] * (H + 1)
    for i in range(1, len(mp)):
        ml = [0 for j in range(N)]
        for j in range(N):
            if i - A[j] < 0:
                ml[j] = mp[0] + B[j]
            else:
                ml[j] = mp[i - A[j]] + B[j]
        mp[i] = min(ml)
    print(mp[-1])   


# Generated by 1.1.6 https://github.com/kyuridenamida/atcoder-tools  (tips: You use the default template now. You can remove this line by using your custom template)
def main():
    def iterate_tokens():
        for line in sys.stdin:
            for word in line.split():
                yield word
    tokens = iterate_tokens()
    H = int(next(tokens))  # type: int
    N = int(next(tokens))  # type: int
    A = [int()] * (N)  # type: "List[int]"
    B = [int()] * (N)  # type: "List[int]"
    for i in range(N):
        A[i] = int(next(tokens))
        B[i] = int(next(tokens))
    solve(H, N, A, B)

if __name__ == '__main__':
    main()