Buggy python submission (verdict: Runtime Error):
import numpy as np

N,M = map(int,input().split())
Xlist = np.array([int(_) for _ in input().split()])
Xlist = np.sort(Xlist)
answer = 0
max_difflist = np.array([])
salist = np.array([])
ilist = np.array([])
min_n = -1

for i in range(M-1):
    sa = abs(Xlist[i]-Xlist[i+1])
    salist = np.append(salist,sa)

    if len(max_difflist)+1 < N:
        ilist = np.append(ilist,i)
        max_difflist = np.append(max_difflist,sa)

    elif sa > min_n:
        max_difflist = np.sort(max_difflist)[::-1]
        index = np.where(max_difflist == min_n)[0]
        max_difflist[index] = sa
        ilist[index] = i
    min_n = np.min(max_difflist)

for i_ in ilist:
    salist[int(i_)] = 0

print(int(sum(salist)))


Fixed submission:
N, M = map(int, input().split())
Xlist = sorted(list(map(int, input().split())))
Llist = []
for i in range(M - 1):
    Llist.append(Xlist[i + 1] - Xlist[i])
Llist.sort()
print(sum(Llist[:M - N]) if N < M else 0)

Buggy python submission (verdict: Runtime Error):
import numpy as np

N,M = map(int,input().split())
Xlist = [int(_) for _ in input().split()]
Xlist.sort()
answer = 0
max_difflist = np.array([])
salist = np.array([])
ilist = np.array([])
min_n = -1

for i in range(M-1):
    sa = abs(Xlist[i]-Xlist[i+1])
    salist = np.append(salist,sa)

    if len(max_difflist)+1 < N:
        ilist = np.append(ilist,i)
        max_difflist = np.append(max_difflist,sa)

    elif sa > min_n:
        max_difflist = np.sort(max_difflist)[::-1]
        index = np.where(max_difflist == min_n)[0]
        max_difflist[index] = sa
        ilist[index] = i
    min_n = np.min(max_difflist)

for i_ in ilist:
    salist[int(i_)] = 0
print(int(sum(salist)))


Fixed submission:
N, M = map(int, input().split())
Xlist = sorted(list(map(int, input().split())))
Llist = []
for i in range(M - 1):
    Llist.append(Xlist[i + 1] - Xlist[i])
Llist.sort()
print(sum(Llist[:M - N]) if N < M else 0)

Buggy python submission (verdict: Runtime Error):
N,M = map(int,input().split())
Xlist = [int(_) for _ in input().split()]
Xlist.sort()
answer = 0
max_difflist = []
salist = []
ilist = []
min_n = -1

for i in range(M-1):
    sa = abs(Xlist[i]-Xlist[i+1])
    salist.append(sa)
    if len(max_difflist) < N-1:
        flg = 1
        ilist.append(i)
        max_difflist.append(sa)
    elif sa > min_n:
        max_difflist.sort(reverse=True)
        index = max_difflist.index(min_n)
        max_difflist[index] = sa
        ilist[index] = i
    min_n = min(max_difflist)

for i_ in ilist:
    salist[i_] = 0
print(sum(salist))


Fixed submission:
N, M = map(int, input().split())
Xlist = sorted(list(map(int, input().split())))
Llist = []
for i in range(M - 1):
    Llist.append(Xlist[i + 1] - Xlist[i])
Llist.sort()
print(sum(Llist[:M - N]) if N < M else 0)

Buggy python submission (verdict: Runtime Error):
N,M = map(int,input().split())
Xlist = [int(_) for _ in input().split()]
Xlist.sort()

answer = 0

max_difflist = []
salist = []
ilist = []
flg = 0
for i in range(M-1):
    if flg == 1:
        min_n = min(max_difflist)
    else:
        min_n = -1
    sa = abs(Xlist[i]-Xlist[i+1])

    salist.append(sa)


    if len(max_difflist) < N-1:
        flg = 1
        ilist.append(i)
        max_difflist.append(sa)
    elif sa > min_n:
        max_difflist.sort(reverse=True)
        index = max_difflist.index(min_n)
        max_difflist[index] = sa
        ilist[index] = i


for i_ in ilist:
    salist[i_] = 0

print(sum(salist))


Fixed submission:
N, M = map(int, input().split())
Xlist = sorted(list(map(int, input().split())))
Llist = []
for i in range(M - 1):
    Llist.append(Xlist[i + 1] - Xlist[i])
Llist.sort()
print(sum(Llist[:M - N]) if N < M else 0)