Question

Write a python while loop that sums all the numbers from m to n, where “m” and “n” are both user given values.

Answer 1

Code with while loop. 

m = int(input("enter the value of m "))
n = int(input("enter the value of n "))

tmp1=m
tmp2=n
sum_till_m=0
while(m>0) :
    sum_till_m +=m
    m = m - 1
sum_till_n = 0
while (n > 0):
    sum_till_n += n
    n = n - 1

if ( tmp1 > tmp2 ) :
    ans = sum_till_m - sum_till_n + tmp2
else :
    ans = sum_till_n - sum_till_m + tmp1

print(ans)

The code without using while loop. but more optimised

m = int(input("enter the value of m "))
n = int(input("enter the value of n "))
sum_till_n = (n*(n+1))/2
sum_till_m = (m*(m+1))/2
if ( m > n ) :
    ans = sum_till_m - sum_till_n + n
else :
    ans = sum_till_n - sum_till_m + m
print(ans)