Question 1 |

Consider the following C code. Assume that unsigned long int type length is 64
bits.

```
unsigned long int fun(unsigned long int n){
unsigned long int i, j = 0, sum = 0;
for (i = n; i > 1; i = i/2) j++;
for ( ; j > 1; j = j/2) sum++;
return(sum);
}
```

The value returned when we call fun with the input 2^{40} is4 | |

5 | |

6 | |

40 |

Question 1 Explanation:

Question 2 |

Consider the C program fragment below which is meant to divide x by y using repeated
subtractions. The variables x, y, q and r are all unsigned int.

```
while (r >= y) {
r = r - y;
q = q +1;
}
```

Which of the following conditions on the variables x, y, q and r before the execution of the
fragment will ensure that the loop terminates in a state satisfying the condition x==(y*q+r)?(q==r) && (r==0) | |

(x \gt 0) && (r==x) && (y \gt 0) | |

(q==0) && (r==x) && (y \gt 0) | |

(q==0) && (y \gt 0) |

Question 2 Explanation:

Question 3 |

The following function computes X^{Y} for positive integers X and Y.

```
int exp(int X,int Y){
int res=1, a=X, b=Y;
while (b!=0){
if(b%2==0){a=a*a; b=b/2;}
else {res=res*a; b=b-1;}
}
return res;
}
```

Which one of the following conditions is TRUE before every iteration of the loop?X^{Y}=a^{b} | |

(res*a)^{Y}=(res*X)^{b} | |

X^{Y}=res*a^{b} | |

X^{Y}=(res*a)^{b} |

Question 3 Explanation:

Question 4 |

The following function computes the maximum value contained in an integer array p[] of size n (n>=1).

```
int max(int*p, int n){
int a=0,b=n-1;
while (__________){
if (p[a]<=p[b]){a=a+1;}
else {b=b-1;}
}
return p[a];
}
```

The missing loop condition isa !=n | |

b !=0 | |

b \gt (a+1) | |

b !=a |

Question 4 Explanation:

Question 5 |

Consider the following pseudo code, where x and y are positive integers.

```
begin
q := 0
r := x
while r \geq y do
begin
r := r - y
q := q + 1
end
end
```

The post condition that needs to be satisfied after the program terminates is{r=qx+y \; \wedge \; r \lt y} | |

{x=qy+r \; \wedge \; r \lt y} | |

{y=qx+r \; \wedge \; 0 \lt r \lt y} | |

{ q+1 \lt r-y \; \wedge \; y \gt 0} |

Question 5 Explanation:

There are 5 questions to complete.

It should be b[m] in question number 9 of loops. Please correct it.

Thank You PRAFUL SAMBHAJI RANE,

We have updated the question.

Confusion between option c and d in question number 10 of loops of c programming.

Answer is option A

C language allows only certain words in it- these are called tokens. If we input any invalid tokens it causes lexical error.

eg:

44a44

causes lexical error as in C as an alphabet cannot come in between digits.

Syntactic error is caused by bad combination of tokens. For example, we cannot have a constant on the left hand side of an assignment statement, a for loop must have two expressions inside () separated by semi colon etc.

In the given question, line 3 won’t cause a lexical error or syntactic error. The statement will be treated as a function call with three arguments. Function definition being absent will cause link time error, but the question asks only for compile-time errors. So, (a) must be the answer.

question number 5, options are:-

A. {r=qx+y∧r<y}

B. {x=qy+r∧r<y}

C. {y=qx+r∧0<r<y}

D. {q+10}

please update it. 😉

Thank You Bikash Dutta,

We have updated the option.