GATE 2015 Official Site

GATE CS 2015 Mock Test

Topic wise solutions of previous year question papers:

Mock tests of previous year papers:

Year wise solutions of previous year question papers:

Topic wise Mock Tests

Data Structures and Algorithms:

Operating Systems:


Compiler Design:

Computer Organization and Architecture:

Computer Networks:

Theory of Computation:


Engineering Mathematics:

Topic wise Reference Books/Material

1) Data Structures and Algorithms:

2) Database Management System

3) Computer Networks

4) Operating Systems

5) Compiler Design

See the previous year questions papers here.

We will be adding more reference books/material soon.

  • ketan

    please provide for digital electronics.

  • gate aspirant

    plzz provide the solution for gate 2013 also

  • roshni mishra

    For Detail syllabus of gate visit GATE Exam Syllabus 2014

  • Somya Jain

    Please send some code re factoring codes example in c or suggest some site for the same.

    /* Paste your code here (You may delete these lines if not writing code) */
  • RM

    Thanks a lot for compiling such useful information at one place.

  • Aruna


    // A structure to represent a Point in 2D plane
    struct Point
    int x, y;

    /* Following two functions are needed for library function qsort().
    Refer: */

    // Needed to sort array of points according to X coordinate
    int compareX(const void* a, const void* b)
    Point *p1 = (Point *)a, *p2 = (Point *)b;
    return (p1->x – p2->x);
    // Needed to sort array of points according to Y coordinate
    int compareY(const void* a, const void* b)
    Point *p1 = (Point *)a, *p2 = (Point *)b;
    return (p1->y – p2->y);

    // A utility function to find the distance between two points
    float dist(Point p1, Point p2)
    return sqrt( (p1.x – p2.x)*(p1.x – p2.x) +
    (p1.y – p2.y)*(p1.y – p2.y)

    // A Brute Force method to return the smallest distance between two points
    // in P[] of size n
    float bruteForce(Point P[], int n)
    float min = FLT_MAX;
    for (int i = 0; i < n; ++i)
    for (int j = i+1; j < n; ++j)
    if (dist(P[i], P[j]) < min)
    min = dist(P[i], P[j]);
    return min;

    // A utility function to find minimum of two float values
    float min(float x, float y)
    return (x < y)? x : y;

    // A utility function to find the distance beween the closest points of
    // strip of given size. All points in strip[] are sorted accordint to
    // y coordinate. They all have an upper bound on minimum distance as d.
    // Note that this method seems to be a O(n^2) method, but it's a O(n)
    // method as the inner loop runs at most 6 times
    float stripClosest(Point strip[], int size, float d)
    float min = d; // Initialize the minimum distance as d

    qsort(strip, size, sizeof(Point), compareY);

    // Pick all points one by one and try the next points till the difference
    // between y coordinates is smaller than d.
    // This is a proven fact that this loop runs at most 6 times
    for (int i = 0; i < size; ++i)
    for (int j = i+1; j < size && (strip[j].y – strip[i].y) < min; ++j)
    if (dist(strip[i],strip[j]) < min)
    min = dist(strip[i], strip[j]);

    return min;

    // A recursive function to find the smallest distance. The array P contains
    // all points sorted according to x coordinate
    float closestUtil(Point P[], int n)
    // If there are 2 or 3 points, then use brute force
    if (n <= 3)
    return bruteForce(P, n);

    // Find the middle point
    int mid = n/2;
    Point midPoint = P[mid];

    // Consider the vertical line passing through the middle point
    // calculate the smallest distance dl on left of middle point and
    // dr on right side
    float dl = closestUtil(P, mid);
    float dr = closestUtil(P + mid, n-mid);

    // Find the smaller of two distances
    float d = min(dl, dr);

    // Build an array strip[] that contains points close (closer than d)
    // to the line passing through the middle point
    Point strip[n];
    int j = 0;
    for (int i = 0; i < n; i++)
    if (abs(P[i].x – midPoint.x) < d)
    strip[j] = P[i], j++;

    // Find the closest points in strip. Return the minimum of d and closest
    // distance is strip[]
    return min(d, stripClosest(strip, j, d) );

    // The main functin that finds the smallest distance
    // This method mainly uses closestUtil()
    float closest(Point P[], int n)
    qsort(P, n, sizeof(Point), compareX);

    // Use recursive function closestUtil() to find the smallest distance
    return closestUtil(P, n);

    // Driver program to test above functions
    int main()
    Point P[] = {{2, 3}, {12, 30}, {40, 50}, {5, 1}, {12, 10}, {3, 4}};
    int n = sizeof(P) / sizeof(P[0]);
    printf("The smallest distance is %f ", closest(P, n));
    return 0;

  • ankush gupta
    From which site can i practice for a page table numerical question
  • shashank
  • harish

    please add some links for Discrete mathematics

  • harish

    helpful for gate prep