a=input('輸入算式')
if?a.count('+')+a.count('-')+a.count('*')+a.count('/')==1?and?a.count('=')==1:
ss=a.split('=')[0]
ans=a.split('=')[1]
for?i?in?'+-*/':
try:
s1=int(ss.split(i)[0])
s2=int(ss.split(i)[1])
ans=int(ans)
if?i=='+':
if?s1+s2==ans:
print('正確')
else:
print('錯誤')
break
if?i=='-':
if?s1-s2==ans:
print('正確')
else:
print('錯誤')
break
if?i=='*':
if?s1*s2==ans:
print('正確')
else:
print('錯誤')
break
if?i=='/':
if?s1/s2==ans:
print('正確')
else:
print('錯誤')
break
except:
pass
else:
print('無法識別')
else:
print('無法識別')