Explore topic-wise MCQs in Engineering.

This section includes 564 Mcqs, each offering curated multiple-choice questions to sharpen your Engineering knowledge and support exam preparation. Choose a topic below to get started.

501.

Is the NULL pointer same as an uninitialised pointer?

A. Yes
B. No
Answer» C.
Discussion
502.

Will the program compile in Turbo C? #include<stdio.h> int main() { int a=10, *j; void *k; j=k=&a; j++; k++; printf("%u %u n", j, k); return 0; }

A. Yes
B. No
Answer» C.
Discussion
503.

Will the following program give any warning on compilation in TurboC (under DOS)? #include<stdio.h> int main() { int *p1, i=25; void *p2; p1=&i; p2=&i; p1=p2; p2=p1; return 0; }

A. Yes
B. No
Answer» C.
Discussion
504.

Which of the following statements correctly declare a function that receives a pointer to pointer to a pointer to a float and returns a pointer to a pointer to a pointer to a pointer to a float?

A. float **fun(float***);
B. float *fun(float**);
C. float fun(float***);
D. float ****fun(float***);
Answer» E.
Discussion
505.

Which of the following are correct preprocessor directives in C? 1: #ifdef 2: #if 3: #elif 4: #undef

A. 1, 2
B. 4
C. 1, 2, 4
D. 1, 2, 3, 4
Answer» E.
Discussion
506.

Which of the following are correctly formed #define statements in C?

A. #define CUBE (X) (X*X*X);
B. #define CUBE(x) (X*X*X)
C. #define CUBE(X)(X*X*X)
D. #define CUBE(X) {X*X*X}
Answer» D. #define CUBE(X) {X*X*X}
Discussion
507.

If the file to be included doesn't exist, the preprocessor flashes an error message.

A. True
B. False
Answer» B. False
Discussion
508.

There exists a way to prevent the same file from getting #included twice in the same program.

A. True
B. False
Answer» B. False
Discussion
509.

A preprocessor directive is a message from programmer to the preprocessor.

A. True
B. False
Answer» B. False
Discussion
510.

Is there any difference between the two statements? char *ch = "IndiaBIX";char ch[] = "IndiaBIX";

A. Yes
B. No
Answer» B. No
Discussion
511.

Will the following code work? #include<stdio.h> #include<malloc.h> struct emp { int len; char name[1]; }; int main() { char newname[] = "Rahul"; struct emp *p = (struct emp *) malloc(sizeof(struct emp) -1 + strlen(newname)+1); p->len = strlen(newname); strcpy(p -> name, newname); printf("%d %s n", p->len, p->name); return 0; }

A. Yes
B. No
Answer» B. No
Discussion
512.

A pointer union CANNOT be created

A. Yes
B. No
Answer» C.
Discussion
513.

For the following statements will arr[3] and ptr[3] fetch the same character? char arr[] = "IndiaBIX";char *ptr = "IndiaBIX";

A. Yes
B. No
Answer» B. No
Discussion
514.

Will the program compile successfully? #include<stdio.h> int main() { char a[] = "India"; char *p = "BIX"; a = "BIX"; p = "India"; printf("%s %s n", a, p); return 0; }

A. Yes
B. No
Answer» C.
Discussion
515.

What will be the output of the program under DOS? #include<stdio.h> int main() { char huge *near *far *ptr1; char near *far *huge *ptr2; char far *huge *near *ptr3; printf("%d, %d, %d n", sizeof(ptr1), sizeof(**ptr2), sizeof(ptr3)); return 0; }

A. 4, 4, 4
B. 4, 2, 2
C. 2, 8, 4
D. 2, 4, 8
Answer» C. 2, 8, 4
Discussion
516.

What will be the output of the program (sample.c) given below if it is executed from the command line (Turbo C in DOS)? cmd> sample 1 2 3 /* sample.c */ #include<stdio.h> int main(int argc, char *argv[]) { int j; j = argv[1] + argv[2] + argv[3]; printf("%d", j); return 0; }

A. 6
B. sample 6
C. Error
D. Garbage value
Answer» D. Garbage value
Discussion
517.

What will be the output of the program? #include<stdio.h> #define SQUARE(x) x*x int main() { float s=10, u=30, t=2, a; a = 2*(s-u*t)/SQUARE(t); printf("Result = %f", a); return 0; }

A. Result = -100.000000
B. Result = -25.000000
C. Result = 0.000000
D. Result = 100.000000
Answer» B. Result = -25.000000
Discussion
518.

In Turbo C/C++ under DOS if we want that any wild card characters in the command-line arguments should be appropriately expanded, are we required to make any special provision?

A. Yes
B. No
Answer» B. No
Discussion
519.

On executing the below program what will be the contents of 'target.txt' file if the source file contains a line "To err is human"? #include<stdio.h> int main() { int i, fss; char ch, source[20] = "source.txt", target[20]="target.txt", t; FILE *fs, *ft; fs = fopen(source, "r"); ft = fopen(target, "w"); while(1) { ch=getc(fs); if(ch==EOF) break; else { fseek(fs, 4L, SEEK_CUR); fputc(ch, ft); } } return 0; }

A. r n
B. Trh
C. err
D. None of above
Answer» C. err
Discussion
520.

Bitwise | can be used to multiply a number by powers of 2.

A. Yes
B. No
Answer» C.
Discussion
521.

How many bytes of memory will the following code reserve? #include<stdio.h> #include<stdlib.h> int main() { int *p; p = (int *)malloc(256 * 256); if(p == NULL) printf("Allocation failed"); return 0; }

A. 65536
B. Allocation failed
C. Error
D. No output
Answer» C. Error
Discussion
522.

Assume integer is 2 bytes wide. What will be the output of the following code? #include<stdio.h> #include<stdlib.h> #define MAXROW 3 #define MAXCOL 4 int main() { int (*p)[MAXCOL]; p = (int (*) [MAXCOL])malloc(MAXROW *sizeof(*p)); printf("%d, %d n", sizeof(p), sizeof(*p)); return 0; }

A. 2, 8
B. 4, 16
C. 8, 24
D. 16, 32
Answer» B. 4, 16
Discussion
523.

Preprocessor directive #undef can be used only on a macro that has been #define earlier

A. True
B. False
Answer» B. False
Discussion
524.

What will be the output of the program ? #include<stdio.h> #include<string.h> int main() { char str1[20] = "Hello", str2[20] = " World"; printf("%s n", strcpy(str2, strcat(str1, str2))); return 0; }

A. Hello
B. World
C. Hello World
D. WorldHello
Answer» D. WorldHello
Discussion
525.

Which statement will you add to the following program to ensure that the program outputs "IndiaBIX" on execution? #include<stdio.h> int main() { char s[] = "IndiaBIX"; char t[25]; char *ps, *pt; ps = s; pt = t; while(*ps) *pt++ = *ps++; /* Add a statement here */ printf("%s n", t); return 0; }

A. *pt='';
B. pt=' 0';
C. pt=' n';
D. *pt=' 0';
Answer» E.
Discussion
526.

What will be the output of the program ? #include<stdio.h> int main() { char p[] = "%d n"; p[1] = 'c'; printf(p, 65); return 0; }

A. A
B. a
C. c
D. 65
Answer» B. a
Discussion
527.

What will be the output of the program ? #include<stdio.h> int main() { union var { int a, b; }; union var v; v.a=10; v.b=20; printf("%d n", v.a); return 0; }

A. 10
B. 20
C. 30
D. 0
Answer» C. 30
Discussion
528.

Nested unions are allowed

A. True
B. False
Answer» B. False
Discussion
529.

What will be the output of the program? #include<stdio.h> int main() { unsigned int res; res = (64 >>(2+1-2)) & (~(1<<2)); printf("%d n", res); return 0; }

A. 32
B. 64
C. 0
D. 128
Answer» B. 64
Discussion
530.

Can we have an array of bit fields?

A. Yes
B. No
Answer» C.
Discussion
531.

To scan a and b given below, which of the following scanf() statement will you use? #include<stdio.h> float a; double b;

A. scanf("%f %f", &a, &b);
B. scanf("%Lf %Lf", &a, &b);
C. scanf("%f %Lf", &a, &b);
D. scanf("%f %lf", &a, &b);
Answer» E.
Discussion
532.

What will be the output of the program? #define P printf("%d n", -1^~0); #define M(P) int main() { P return 0; } M(P)

A. 1
B. <span>0</span>
C. -1
D. 2
Answer» C. -1
Discussion
533.

What will be the output of the program? #include&lt;stdio.h&gt; int get(); int main() { const int x = get(); printf("%d", x); return 0; } int get() { return 20; }

A. Garbage value
B. Error
C. 20
D. 0
Answer» D. 0
Discussion
534.

Will the program outputs "IndiaBIX.com"? #include&lt;stdio.h&gt; #include&lt;string.h&gt; int main() { char str1[] = "IndiaBIX.com"; char str2[20]; strncpy(str2, str1, 8); printf("%s", str2); return 0; }

A. Yes
B. No
Answer» C.
Discussion
535.

Which of the following is the correct usage of conditional operators used in C?

A. a>b ? c=30 : c=40;
B. a>b ? c=30;
C. max = a>b ? a>c?a:c:b>c?b:c
D. return (a>b)?(a:b)
Answer» D. return (a>b)?(a:b)
Discussion
536.

What will be the output of the program? #include&lt;stdio.h&gt; #include&lt;math.h&gt; int main() { float n=1.54; printf("%f, %f n", ceil(n), floor(n)); return 0; }

A. 2.000000, 1.000000
B. 1.500000, 1.500000
C. 1.550000, 2.000000
D. 1.000000, 2.000000
Answer» B. 1.500000, 1.500000
Discussion
537.

What will be the output of the program? #include&lt;stdio.h&gt; int main() { float d=2.25; printf("%e,", d); printf("%f,", d); printf("%g,", d); printf("%lf", d); return 0; }

A. 2.2, 2.50, 2.50, 2.5
B. 2.2e, 2.25f, 2.00, 2.25
C. 2.250000e+000, 2.250000, 2.25, 2.250000
D. Error
Answer» D. Error
Discussion
538.

If a function contains two return statements successively, the compiler will generate warnings. Yes/No ?

A. Yes
B. No
Answer» B. No
Discussion
539.

What will be the output of the program? #include&lt;stdio.h&gt; #include&lt;stdlib.h&gt; int main() { union test { int i; float f; char c; }; union test *t; t = (union test *)malloc(sizeof(union test)); t-&gt;f = 10.10f; printf("%f", t-&gt;f); return 0; }

A. 10
B. Garbage value
C. 10.100000
D. Error
Answer» D. Error
Discussion
540.

Assume integer is 2 bytes wide. How many bytes will be allocated for the following code? #include&lt;stdio.h&gt; #include&lt;stdlib.h&gt; #define MAXROW 3 #define MAXCOL 4 int main() { int (*p)[MAXCOL]; p = (int (*) [MAXCOL])malloc(MAXROW *sizeof(*p)); return 0; }

A. 56 bytes
B. 128 bytes
C. 24 bytes
D. 12 bytes
Answer» D. 12 bytes
Discussion
541.

We can allocate a 2-Dimensional array dynamically.

A. True
B. False
Answer» B. False
Discussion
542.

Function can return a floating point number.

A. True
B. False
Answer» B. False
Discussion
543.

malloc() returns a float pointer if memory is allocated for storing float's and a double pointer if memory is allocated for storing double's.

A. True
B. False
Answer» C.
Discussion
544.

malloc() allocates memory from the heap and not from the stack.

A. True
B. False
Answer» B. False
Discussion
545.

Point out the correct statement which correctly allocates memory dynamically for 2D array following program? #include&lt;stdio.h&gt; #include&lt;stdlib.h&gt; int main() { int *p, i, j; /* Add statement here */ for(i=0; i&lt;3; i++) { for(j=0; j&lt;4; j++) { p[i*4+j] = i; printf("%d", p[i*4+j]); } } return 0; }

A. p = (int*) malloc(3, 4);
B. p = (int*) malloc(3*sizeof(int));
C. p = malloc(3*4*sizeof(int));
D. p = (int*) malloc(3*4*sizeof(int));
Answer» E.
Discussion
546.

typedef's have the advantage that they obey scope rules, that is they can be declared local to a function or a block whereas #define's always have a global effect.

A. Yes
B. No
Answer» B. No
Discussion
547.

Can I increase the size of dynamically allocated array?

A. Yes
B. No
Answer» B. No
Discussion
548.

Is the following declaration acceptable? typedef long no, *ptrtono; no n; ptrtono p;

A. Yes
B. NO
Answer» B. NO
Discussion
549.

malloc() returns a NULL if it fails to allocate the requested memory.

A. True
B. False
Answer» B. False
Discussion
550.

If malloc() successfully allocates memory it returns the number of bytes it has allocated.

A. True
B. False
Answer» C.
Discussion