Aptitude Answers:

1. I hate sitting - beside 
2. Owl cannot - an 
3. Higher you climb, - the,the 
4. He can read - the 
5. You cannot send out - an,the 
6. The crowd waited - until 
7. Ever since he bought - at 
8. She is - an 
9. In Park I saw - the,a 
10. I cannot go - since 
11. If you believe- in 
12. The parcel - in 
13. He became - a 
14. The food will be - in 
15. Sun shines - the 
16. The students voiced - by 
17. Life is not - a
18. Although no one - on 
19. The man - from
20. Rajesh was - until



Program Solutions:

#Sum of Last X Digits 

n=int(input())
x=int(input())
s=0
for i in range(x):
    s+=n%10 
    n=n//10 
print(s)

#Product of Current and Next Elements 

n=int(input())
l=list(map(int,input().split()))
for i in range(n):
    if(i==n-1):
        print(l[i])
    elif(l[i]>l[i+1]):
        print(l[i]*l[i+1],end=" ")
    else:
        print(l[i],end=" ")

#Product of Three Integers

a,b,c=map(int,input().split())
print(a*b*c)

#Interlaced String 
s1=input().strip()
s2=input().strip()
j=0
for i in s2[::-1]:
    print(i,end="")
    if(j<len(s1)):
        print(s1[j],end="")
        j+=1 
if(len(s2)<len(s1)):
    print(s1[j:])