Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
ls = []
if len(li) - 1 < n - 1:
    print(0)
else:
    list.sort(li)
    for i in range(len(li) - 1):
        ls.append(li[i + 1] - li[i])
    for j in range(n - 1):
        ls.remove(max(ls))
    print(sum(ls))

Fixed submission:
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
ls = []
list.sort(li)
for i in range(len(li) - 1):
    ls.append(li[i + 1] - li[i])
ls = sorted(ls, reverse=True)
print(sum(ls[n-1:]))

Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
list.sort(li)
ls = []
if len(li) - 1 < n - 1:
    print(0)
else:
    for i in range(len(li) - 1):
        ls.append(li[i + 1] - li[i])
    for j in range(n - 1):
        ls.remove(max(ls))
    print(sum(ls))

Fixed submission:
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
ls = []
list.sort(li)
for i in range(len(li) - 1):
    ls.append(li[i + 1] - li[i])
ls = sorted(ls, reverse=True)
print(sum(ls[n-1:]))

Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
list.sort(li)
ls = []
for i in range(len(li)-1):
    ls.append(li[i+1]-li[i])
if len(ls) < n - 1:
    print(0)
else:
    for j in range(n - 1):
        ls.remove(max(ls))
    print(sum(ls))

Fixed submission:
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
ls = []
list.sort(li)
for i in range(len(li) - 1):
    ls.append(li[i + 1] - li[i])
ls = sorted(ls, reverse=True)
print(sum(ls[n-1:]))

Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
list.sort(li)
ls = []
for i in range(len(li)-1):
    ls.append(li[i+1]-li[i])
if len(ls) < n - 1:
    print(0)
else:
    for j in range(n - 1):
        if len(ls) > 0:
            ls.remove(max(ls))
    print(sum(ls))

Fixed submission:
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
ls = []
list.sort(li)
for i in range(len(li) - 1):
    ls.append(li[i + 1] - li[i])
ls = sorted(ls, reverse=True)
print(sum(ls[n-1:]))

Buggy python submission (verdict: Time Limit Exceeded):
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
list.sort(li)
ls = []
for i in range(len(li)-1):
    ls.append(li[i+1]-li[i])
for j in range(n - 1):
    if len(ls) > 0:
        ls.remove(max(ls))
print(sum(ls))

Fixed submission:
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
ls = []
list.sort(li)
for i in range(len(li) - 1):
    ls.append(li[i + 1] - li[i])
ls = sorted(ls, reverse=True)
print(sum(ls[n-1:]))

Buggy python submission (verdict: Runtime Error):
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
list.sort(li)
ls = []
for i in range(len(li)-1):
    ls.append(li[i+1]-li[i])
for j in range(n - 1):
    ls.remove(max(ls))
print(sum(ls))

Fixed submission:
import sys

stdin = sys.stdin

ni = lambda: int(ns())
na = lambda: list(map(int, stdin.readline().split()))
ns = lambda: stdin.readline().rstrip()  # ignore trailing spaces

n, m = na()
li = na()
ls = []
list.sort(li)
for i in range(len(li) - 1):
    ls.append(li[i + 1] - li[i])
ls = sorted(ls, reverse=True)
print(sum(ls[n-1:]))