Problem Set on If Statements and For Loops

For what possible values of x are statements A and B executed in the following two pieces of code?

First piece of code:

if (x >= 3):
    if (x == 7):
       statement A 

    else:
	statement B

Second piece of code:

if (x >= 3):
    if (x == 7):
       statement A 
else:
   statement B

Explain the difference between the following two pieces of code. For each piece of code assume that the variables x and y have been defined and assigned a value before reaching this section.
1. First piece of code:
```
s = 0
if ( x > 0 ):
    s = s + 1
if ( y > 0 ):
    s = s + 1
```
2. Second piece of code:
```
s = 0
if ( x > 0 ):
    s = s + 1
elif ( y > 0 ):
    s = s + 1
```
What does the following for statement do? Assume that n is some positive integer.
```
for b in range(1, n, 2):
    print b
```

For the following loops, indicate what will be printed.

First piece of code:

for x in range(4):
   for y in range(2, 4):
       print x , y

Second piece of code:

for x in range(4):
   for y in range(x, 4):
       print x , y