Hi Pookies

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13 Write a C program to print all alphabets from a to z.
#include <stdio.h>
int main()
{
    char c;
    for(c = 'A'; c <= 'Z'; c++)
    {
        printf("%c", c);
    }
    return 0;
}
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14 Write a C program to print all even numbers between 1 to 100
#include <stdio.h>
int main()
{   
    for(int i = 1; i <= 100; i++)
    {
        if(i % 2 == 0)
        {
            printf("%d \n", i);
        }
    }
    return 0;
}
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15 Write a C program to find sum of all odd numbers between 1 to n.
#include <stdio.h>
int main()
{   
    int n; int total;
    total = 0;
    scanf("%d", &n);
    for(int i = 1; i <= n; i++ )
    {
        if(i % 2 == 1)
        {
            total += i;
        }
    }
    printf("The Total is %d", total);
    return 0;
}
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16 Write a C program to print multiplication table of any number.
#include <stdio.h>
int main()
{
    int n;
    scanf("%d", &n);
    for(int i = 1; i <= 10; i++)
    {
        printf("%d x %d = %d \n", i, n, n*i);
    }
    return 0;
}
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17 Write a C program to count number of digits in a number.
#include <stdio.h>
int main()
{
    int n; 
    scanf("%d", &n);
    if(n == 0){return 1;}
    int count = 0;
    while (n != 0) {
        count++;
        n /= 10;
    }
    printf("Number of Digits: %d", count);
    return 0;
}
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18 Write a C program to find first and last digit of a number.
#include <stdio.h>
int main() {
    int num, firstDigit, lastDigit;
    printf("Enter a number: ");
    scanf("%d", &num);
    if(num < 10)
    {
        printf("Invalid. Number is less than 10");
        return 0;
    }
    // Find the last digit
    lastDigit = num % 10;
    // Find the first digit
    while (num >= 10) {
        num /= 10;
    }
    firstDigit = num;
    printf("First digit: %d\n", firstDigit);
    printf("Last digit: %d\n", lastDigit);
    return 0;
}
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19
#include <stdio.h>
int swap_first_last(int num) {
    int last_digit, first_digit, divisor = 1, temp_num = num;
    last_digit = num % 10;
    while (temp_num >= 10) {
        temp_num /= 10;
        divisor *= 10;
    }
    first_digit = temp_num;
    num = num - first_digit * divisor; 
    num = num - last_digit;           
    num = num + first_digit;        
    num = num + last_digit * divisor; 
    return num;
}
int main() {
    int number;
    printf("Number plz: ");
    scanf("%d", &number);
    int swapped_number = swap_first_last(number);
    printf("Original number: %d\n", number);
    printf("Swapped number: %d\n", swapped_number);
    return 0;
}
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20 Write a C program to find frequency of each digit in each integer.
#include <stdio.h>
int main()
{
    int n, dE;
    int aon[10]; 
    if (n < 0) {
        printf("Invalid input. Make sure to use a positive number.");
        return 0;
    }
    printf("Input Number:");
    scanf("%d", &n);
    while(n >= 10)
    {
        dE = n % 10; 
        aon[dE]++;
        n /= 10;
    }
    int ld;
    ld = n;
    aon[n]++;
    for(int i = 0; i < 10; i++)
    {
        printf("Number %d, Frequencies %d: \n", i, aon[i]);
    }
}
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21 Write a C program to enter a number and print it in words.
#include <stdio.h>
int printn(int n)
{
    switch (n){
        case 1:
            printf("One ");
            break;
        case 2:
            printf("Two ");
            break;
        case 3:
            printf("Three ");
            break;
        case 4:
            printf("Four ");
            break;
        case 5:
            printf("Five ");
            break;
        case 6:
            printf("Six ");
            break;
        case 7:
            printf("Seven ");
            break;
        case 8:
            printf("Eight ");
            break;
        case 9:
            printf("Nine ");
            break;
        case 0:
            printf("Zero ");
            break;
    } 
}
int main()
{
    int n;
    printf("Enter n: ");
    scanf("%d", &n);
    while(n >= 10)
    {
        checkWork(n % 10);
        n /= 10;
    }
    printn(n);
    return 0;
}