a = 1;
b = 2;
c = a + b 
print (c)
3
import time
starttime = time.time()
product = 1
for i in range(1 ,100):
    product = product * i
endtime = time.time()
print('The result is %s digits long.'%(len(str(product))))
print('took %s seconds to calculate'%(endtime-starttime))
The result is 156 digits long.
took 0.00014781951904296875 seconds to calculate
print ("Enter A")
A = input()
import time 
starttime = time.time()
s = 0
for i in range(1, A):
    s = s + i
    
endtime = time.time()
print (sum)
print ('took %s seconds to calculate'%(endtime-starttime))
    
    
Enter A
4
---------------------------------------------------------------------------
TypeError                                 Traceback (most recent call last)
<ipython-input-35-422190daf25d> in <module>()
      4 starttime = time.time()
      5 s = 0
----> 6 for i in range(1, A):
      7     s = s + i
      8 

TypeError: 'str' object cannot be interpreted as an integer