Question

Need help with these questions in C programming:

9. What is the output of the following code? int X[10]={0}; int N=4; for(int k=0; k<N:k++) X[k] = k*2: printf("%d", X[N/2]; 10. Write a single statement to accomplish each of the following. Assume that each of these statements applies to the same program. a. Write a statement that opens file "oldmast.dat" for reading and assigns the returned file pointer to ofPtr. b. Write a statement that opens file "trans.dat" for writing and assigns the returned file pointer to tfPtr. 11. Give the following declaration: int il; int i2: float fl; char cl; char c2: and the following line of data 11 23 79 AB What would be the value of il, i2, fl,cl and c2 after the following statement? scanf("%d %d %f %c %c",&il, &i2, &fi,&c1,&c2); 12. If x=0, y =5, z=5, what is the value of x, y and z after the following code? If(z!=0) y=1; else x = 10;

Answer 1

9. This program will generate a compilation error.
because in the statement
printf("%d",X[N/2];
There is no closing bracket. so there will be an error

but if we solve the error the output generated for the program is:
0,0,4,4

The array is initially initialized to 0. at every iteration the value of k*2 is getting inserted into the array
In the print statement it is printing X[N/2]
N=4
so X[N/2]=X[4/2]=X[2]
in the first 2 iterations X[2] is not initialized yet hence X[2] is given 0
in the last 2 iterations X[2] is generated as 4, so it will be printed.

program:

#include<stdio.h> int main() int X[10]={@}; int N=4; for(int k=0; k<N;k++) X[k]=k*2; printf("%d,",X[N/2]);

Output:

0,4,4, Process exited after 0.01832 seconds with return value @ Press any key to continue . . .

==========================================================================================

10.
a.
ofPtr = fopen("oldmast.dat","r");

opening the file oldmast.dat using fopen function in read mode ("r"). Assigning to file pointer ofPtr

b.
tfPtr = fopen("trans.dat","w");

opening the file trans.dat using fopen funtion in write mode ("w")

============================================================================================

11.

value of
i1 = 11
i2 = 23
f1 = 79.0
c1 = A
c2 = B

============================================================================================

12.
After the execution of the given code, the value of x,y and z will be:
x=0
y=1
z=5