Question

11. What is the output of the following section of a program?

int a[8] = {2, 5, 1, 0, 0, 0, 0, 0};
for(int i=7;i>0;i--)
a[i]=a[i -1];
for(int k=0;k<8;k++)
cout< 14 years ago

Answer 1

I am not sure, i'd like to know the proper reason too, but i think its because of a[i]=a[i-1].

Answer 2

the loop goes from 7 down to 1
and it copies the previous (in the array) value each time

you can get a much better answer to questions like this by either
1) single stepping through the code if your environment supports it OR
2) setting a breakpoint in the loop and using the debugger to browse

Answer 3

Because your last iteration through the loop, when i = 1, it copies a[0] to a[1] and exits. So all of the values are moved over one location--replacing the original value--with the exception of a[0] because there is no mechanism that replaces the initial value.

Answer 4

in the loop for(i=7;i>0;i--) on encountering the statement a[i]=a[i-1] ie, a[7]=a[6],a[6]=a[5],a[5]=a[4],a[4]=a[3],a[3]=a[2],a[2]=a[1],a[1]=a[0] the array will come in the order 2 2 5 1 0 0 0 0 after that in the next loop v r just printing the array

Answer 5

before execution of first loop:a[7]=0,a[6]=0,a[5]=0,a[4]=0,a[3]=0,a[2]=1,a[1]=5,a[0]=2
after the first for loop: a[7]=a[6]=0
similarly, a[3]=a[2]=1
a[2]=a[1]=5
a[1]=a[0]=2
here loop exits
and value of a[0] is unchanged
so the result will come
a[0]=2, a[1]=2, a[2]=5 .........