Buggy python submission (verdict: Time Limit Exceeded):
import sys
sys.setrecursionlimit(10**9)

H, N = map(int, input().split())
magic = [_ for _ in range(N)]

for k in range(N):
  magic[k] = list(map(int, input().split()))
  magic[k].append(magic[k][0]/magic[k][1])

magic.sort(key = lambda x: x[2], reverse=True)
ans = [0 for _ in range(H+1)]
visited = [0]
anskouho = []

def solve(start, power, point, maryoku):
  if start >= H:
    anskouho.append(point)
    visited.sort(reverse=True)
    return 0
  elif ans[start] != 0:
    visited.sort(reverse=True)
    return 0
  else:
    visited.append(start)
    ans[start] = point
    solve(start+power, power, point+maryoku, maryoku)

for k in range(N):
  for item in visited:
    solve(item+magic[k][0], magic[k][0], ans[item] + magic[k][1], magic[k][1])

print(min(anskouho))


Fixed submission:
import sys
sys.setrecursionlimit(10**9)

H, N = map(int, input().split())
magic = [_ for _ in range(N)]

for k in range(N):
  magic[k] = list(map(int, input().split()))
  magic[k].append(magic[k][0]/magic[k][1])

magic.sort(key = lambda x: x[2], reverse=True)
ans = [0 for _ in range(H+1)]
visited = [0]
anskouho = [float('inf')]

def solve(start, power, point, maryoku):
  if start == H:
    print(min(point, min(anskouho)))
    exit()
  elif start > H:
    anskouho.append(point)
    visited.sort(reverse=True)
    return 0
  elif ans[start] != 0:
    visited.sort(reverse=True)
    return 0
  else:
    visited.append(start)
    ans[start] = point
    solve(start+power, power, point+maryoku, maryoku)

for k in range(N):
  for item in visited:
    solve(item+magic[k][0], magic[k][0], ans[item] + magic[k][1], magic[k][1])

print(min(anskouho))

Buggy python submission (verdict: Time Limit Exceeded):
import sys
sys.setrecursionlimit(10**9)

H, N = map(int, input().split())
magic = [_ for _ in range(N)]

for k in range(N):
  magic[k] = list(map(int, input().split()))
  magic[k].append(magic[k][0]/magic[k][1])

magic.sort(key = lambda x: x[2], reverse=True)
ans = [0 for _ in range(H+1)]
visited = [0]
anskouho = []

def solve(start, power, point, maryoku):
  if start >= H:
    anskouho.append(point)
    visited.sort(reverse=True)
    return 0
  elif ans[start] != 0:
    visited.sort(reverse=True)
    return 0
  else:
    visited.append(start)
    ans[start] = point
    solve(start+power, power, point+maryoku, maryoku)

for k in range(N):
  for item in visited:
    solve(item+magic[k][0], magic[k][0], ans[item] + magic[k][1], magic[k][1])

print(min(anskouho))

Fixed submission:
import sys
sys.setrecursionlimit(10**9)

H, N = map(int, input().split())
magic = [_ for _ in range(N)]

for k in range(N):
  magic[k] = list(map(int, input().split()))
  magic[k].append(magic[k][0]/magic[k][1])

magic.sort(key = lambda x: x[2], reverse=True)
ans = [0 for _ in range(H+1)]
visited = [0]
anskouho = [float('inf')]

def solve(start, power, point, maryoku):
  if start == H:
    print(min(point, min(anskouho)))
    exit()
  elif start > H:
    anskouho.append(point)
    visited.sort(reverse=True)
    return 0
  elif ans[start] != 0:
    visited.sort(reverse=True)
    return 0
  else:
    visited.append(start)
    ans[start] = point
    solve(start+power, power, point+maryoku, maryoku)

for k in range(N):
  for item in visited:
    solve(item+magic[k][0], magic[k][0], ans[item] + magic[k][1], magic[k][1])

print(min(anskouho))