同符号数学运算

N=eval(input())
t=0
if N<0:
n1=-N+10
n2=-N-10
n3=-N*10
t=-1
else:
n1=N+10
n2=N-10
n3=N*10
t=1
if n1<0:
n1=-n1
if n2<0:
n2=-n2
if n3<0:
n3=-n3
print(t*N,n1*t,n2*t,n3*t)

来源：https://www.cnblogs.com/2640335699qqcom/p/12561351.html