IBM Placement Paper - Programming Question And Answers

IBM Previous Years Solved Sample Placement Papers

Find GCD or HCF of Two Numbers

#include <iostream>
using namespace std;
int gcd(int a, int b)
{
    int result = min(a, b); 
    while (result > 0) {
        if (a % result == 0 && b % result == 0) {
            break;
        }
        result--;
    }
    return result; 
}
int main()
{
    int a = 98, b = 56;
    cout << "GCD of " << a << " and " << b << " is " << gcd(a, b);
    return 0;
}
            

Check if a Year is Leap Year

#include <bits/stdc++.h>
using namespace std;
bool checkYear(int year)
{
    if (year % 400 == 0)
        return true;
    if (year % 100 == 0)
        return false;
    if (year % 4 == 0)
        return true;
    return false;
}
int main()
{
    int year = 2000;
    checkYear(year) ? cout << "Leap Year" : cout << "Not a Leap Year";
    return 0;
}
            

Reverse Digits of a Number

#include <bits/stdc++.h>
using namespace std;
int reverseDigits(int num)
{
    int rev_num = 0;
    while (num > 0) {
        rev_num = rev_num * 10 + num % 10;
        num = num / 10;
    }
    return rev_num;
}
int main()
{
    int num = 4562;
    cout << "Reverse of no. is " << reverseDigits(num);
    getchar();
    return 0;
}
            

Check if a String is Palindrome

#include <stdio.h>
#include <string.h>
int main()
{
    char str[] = { "abbba" };
    int l = 0;
    int h = strlen(str) - 1;
    while (h > l) {
        if (str[l++] != str[h--]) {
            printf("%s is not a palindrome\n", str);
            return 0;
        }
    }
    printf("%s is a palindrome\n", str);
    return 0;
}
            

Print All Prime Numbers Less Than or Equal to N

#include <bits/stdc++.h>
using namespace std;
bool isPrime(int n)
{
    if (n <= 1)
        return false;
    for (int i = 2; i < n; i++)
        if (n % i == 0)
            return false;
    return true;
}
void printPrime(int n)
{
    for (int i = 2; i <= n; i++)
        if (isPrime(i))
            cout << i << " ";
}
int main()
{
    int n = 7;
    printPrime(n);
}
            

Sum of the Digits of a Number

#include <iostream>
using namespace std;
class PrepBytes {
public:
    int getSum(int n)
    {
        int sum;
        for (sum = 0; n > 0; sum += n % 10, n /= 10)
            ;
        return sum;
    }
};
int main()
{
    PrepBytes g;
    int n = 687;
    cout << g.getSum(n);
    return 0;
}
            

Concatenate Two Strings in C++

#include <bits/stdc++.h>
using namespace std;
int main()
{
    char init[] = "this is init";
    char add[] = " added now";
    // concatenating the string.
    strcat(init, add);
    cout << init << endl;
    return 0;
}
            

Find LCM of Two Numbers

#include <iostream>
using namespace std;
long long gcd(long long int a, long long int b)
{
    if (b == 0)
        return a;
    return gcd(b, a % b);
}
long long lcm(int a, int b)
{
    return (a / gcd(a, b)) * b;
}
int main()
{
    int a = 15, b = 20;
    cout << "LCM of " << a << " and " << b << " is " << lcm(a, b);
    return 0;
}
            

Swap Two Numbers Without a Temporary Variable

#include <bits/stdc++.h>
using namespace std;
int main()
{
    int x = 10, y = 5;
    // Code to swap 'x' and 'y'
    x = x + y; // x now becomes 15
    y = x - y; // y becomes 10
    x = x - y; // x becomes 5
    cout << "After Swapping: x =" << x << ", y=" << y;
}
            

Check if a Number is Palindrome

#include <iostream>
using namespace std;
int oneDigit(int num)
{
    return (num >= 0 && num < 10);
}
bool isPalUtil(int num, int* dupNum)
{
    if (oneDigit(num))
        return (num == (*dupNum) % 10);
    if (!isPalUtil(num / 10, dupNum))
        return false;
    *dupNum /= 10;
    return (num % 10 == (*dupNum) % 10);
}
int isPal(int num)
{
    if (num < 0)
        num = -num;
    int* dupNum = new int(num);
    return isPalUtil(num, dupNum);
}
int main()
{
    int n = 12321;
    isPal(n) ? cout << "Yes\n" : cout << "No" << endl;
    n = 12;
    isPal(n) ? cout << "Yes\n" : cout << "No" << endl;
    n = 88;
    isPal(n) ? cout << "Yes\n" : cout << "No" << endl;
    n = 8999;
    isPal(n) ? cout << "Yes\n" : cout << "No";
    return 0;
}