Use of conditional statements-Using switch in C language.

Use of switch in C language.

 #include <stdio.h>

int main(int argc, char const *argv[])

{

    int a=11;

    while (a != 10)

    {

        // switch case

        printf("Enter Number :");

        scanf("%d", &a);

        switch (a)

        {

        case 0:

        {

            printf("%d :zero is the number.\n", a);

            break;

        }

        case 1:

        {

            printf("%d :one is the number.\n", a);

            break;

        }

        case 2:

        {

            printf("%d :two is the number.\n", a);

            break;

        }

        case 3:

        {

            printf("%d :three is the number.\n", a);

            break;

        }

        default:

        {

            printf("Not valid input.\n");

            break;

        }

        }

    }

    return 0;

}

Hacker-rank problem -marks sum problem of students. ( C language )

//Hackerrank problem -marks sum problem of students.

#include <stdio.h>

#include <string.h>

#include <math.h>

#include <stdlib.h>

int marks_summation(int* marks , int number_of_students , char gender)

{

    int sum = 0 , i;

    if ( gender == 'b' )

    {

        for ( int i = 0; i < number_of_students; i += 2 )

        {

            sum += marks[i];

        }

    }

    else

    {

        for ( int i = 1; i < number_of_students; i += 2 )

        {

            sum += marks[i];

        }

    }

    return sum;

}

int main()

{

    int number_of_students;

    char gender;

    int sum;

    scanf("%d" , &number_of_students);

    int* marks = (int*)malloc(number_of_students * sizeof(int));

    for ( int student = 0; student < number_of_students; student++ )

    {

        scanf("%d" , (marks + student));

    }

    scanf(" %c" , &gender);

    sum = marks_summation(marks , number_of_students , gender);

    printf("%d" , sum);

    free(marks);

    return 0;

}

Euler Problem-finding difference between sum of square and square of sum problem. ( C language )

solving maths problems using C language.

 /*

The sum of the squares of the first ten natural numbers is,

 1^2 + 2^2 + 3^2 + ... 10^2 = 385

The square of the sum of the first ten natural numbers is,

(1+2+3+4...........+10)^2 = 3025

Hence the difference between the sum of the squares of the first ten natural numbers

 and the square of the sum is .

 3025-385=2640

Find the difference between the sum of the squares of the first one hundred

natural numbers and the square of the sum.

 */

#include <stdio.h>

int main()

{

    int sum_upto;

    sum_upto = 100;

    int sum_of_squares = 0;

    int square_of_sum = 0;

    for (int i = 1; i <= sum_upto; i++)

    {

        sum_of_squares += (i * i);

        square_of_sum += ( i );

    }

    square_of_sum *= square_of_sum;

    int diff = square_of_sum - sum_of_squares;

    printf("Difference is : %d", diff);

    return 0;

}

Use of mathematical operations and implementation (C language )

Problem-Finding the sum of digits of five digit number.

 #include <stdio.h>

#include <string.h>

#include <math.h>

#include <stdlib.h>

int main()

{

    int n;

    scanf("%d", &n);

    // Complete the code to calculate the sum of the five digits on n.

    int num;

    int base = 10000;

    int sum = 0;

    // printf("%d\n",(num-(num%base))/base );

    // printf("%d\n",(num%base));

    for (int i = 1; i <= 5; i++)

    {

        num = (n - (n % base)) / base;

        n = (n % base);

        base /= 10;

        sum += num;

    }

    printf("%d\n", sum);

    return 0;

}

Example through learning datatypes and mathematical operations ( C language)

Mathematical operations using float and integers.

 #include <stdio.h>

#include <string.h>

#include <math.h>

#include <stdlib.h>

int main()

{

    int a, b;

    float c, d;

    scanf("%d",&a);

    scanf("%d",&b);

    printf("\n");

    scanf("%f",&c);

    scanf("%f",&d);

    printf("%d %d\n", a + b, a - b);

    printf("%.1f %.1f", c + d, c - d);

    return 0;

}

Characters and Strings in C language

More string operations in C language

 #include <stdio.h>

#include <string.h>

#include <math.h>

#include <stdlib.h>

int main()

{

    char ch;

    char str[10];

    char sen[25];

    scanf("%c", &ch);

    scanf("%s", str);

    scanf("\n");

    scanf("%[^\n]%*c", sen);

    printf("%c\n", ch);

    printf("%s\n", str);

    printf("%s", sen);

    return 0;

}

Character arrays in C (Strings)

Operations on Strings (input and output)

 #include <stdio.h>

#include <string.h>

int main()

{

    char string1[] = "stringA";

    char string2[] = "stringa";

    int arr_size = sizeof(string1) / sizeof(char);

    // printing string

    printf("%s \n" , string1);

    printf("%c \n" , *string1);

    printf("%s \n" , string1);

    //comparing strings

    int diff = strcmp(string1 , string2);

    printf("%d \n" , diff);

//function to take input of the string type by user

    fgets(string1 , arr_size , stdin);

    //printing string using loop

    for ( int i = 0; i < arr_size; i++ )

    {

        printf("%c" , *(string1 + i));

    }

    return 0;

}

HackerRank -Pointers in C (C Language)

Operations on pointers-finds the sum and difference between numbers given.

 #include <stdio.h>

void update(int* a , int* b) {

    int temp = *a;

    *a = temp + *b;

    *b = temp - *b;

    if (*b < 0)

    {

        *b *= (-1);

    }

}

int main() {

    int a , b;

    int* pa = &a , * pb = &b;

    printf("Enter two Numbers : ");

    scanf("%d %d" , &a , &b);

    update(pa , pb);

    printf(" sum : %d\n Difference : %d" , a , b);

    return 0;

}

Euler Problem-Printing the pattern (C language)

Printing the patterns of number.

 /*

printing the pattern as given below for given number--

3 3 3 3 3

3 2 2 2 3

3 2 1 2 3

3 2 2 2 3

3 3 3 3 3

*/

#include <stdio.h>

int main()

{

    int n;

    printf("Enter : ");

    scanf("%d" , &n);

    // Complete the code to print the pattern.

    for (int i = 0; i < (2 * n) - 1; i++)

    {

        for (int j = 0; j < (2 * n) - 1; j++)

        {

            int min = i < j ? i : j;

            min = min < (2 * n - j - 2) ? min : (2 * n - j - 2);

            min = min < (2 * n - i - 2) ? min : (2 * n - i - 2);

            int index = n - (min);

            printf("%d " , index);

        }

        printf("\n");

    }

    return 0;

}