#include<stdio.h>
#include<stdlib.h>
#include<string.h>
char ch[200];

void print() {
    printf("\nEnter the message: ");
    gets(ch);
}

void ntime() {
    int n, i;
    n = strlen(ch);
    printf("The above message is printed %d times below:", n);
    for (i = 0; i < n; i++)
        printf("\n%s", ch);
    printf("\n");
}

void revo() {
    printf("The message in reverse order is: ");
    printf("%s\n", strrev(ch));
}

void change() {
    int i, j;
    i = strlen(ch);
    for (j = 0; j < i; j++) {
        if (ch[j] >= 'a' && ch[j] <= 'z')
            ch[j] -= 32;
        else if (ch[j] >= 'A' && ch[j] <= 'Z')
            ch[j] += 32;
        else
            continue;
    }
    puts(ch);
}

void block() {
    int i, j, n;
    n = strlen(ch);
    printf("The given message in block staircase pattern is: \n");
    for (i = 0; i < n; i++) {
        for (j = 0; j <= i; j++)
            printf("%c", ch[j]);
        printf("\n");
    }
    printf("\n");
}

void main() {
    int a;
    while (1) {
        printf("\nMENU");
        printf("\n1.Print message no. of time as per its length");
        printf("\n2.Print the message in reverse order");
        printf("\n3.Print the message in block staircase pattern");
        printf("n4.Print the message in capital letters and vice versa");
        printf("\n5.Exit from program");
        printf("\n\nEnter your choice: ");
        scanf("%d", &a);
        switch (a) {
        case 1:
            ntime();
            break;
        case 2:
            revo();
            break;
        case 3:
            block();
            break;
        case 4:
            change();
            break;
        case 5:
            exit(1);
        default:
            printf("Invalid choice\n");
        }
    }
}

#include<stdio.h>
#include<stdlib.h>
#include<math.h>

void lucky();
float ctof();
float sqr();
long int fact();
int a;
void main() {
    int ch;
    while (1) {
        printf("\nMENU");
        printf("\n1.%cC to %cF conversion\n2.Square root of a number");
        printf("\n3.10 Lucky numbers between two numbers");
        printf("\n4.Factorial of given number");
        printf("\n9.Abandon the program",248,248);
        printf("\n\nEnter your choice: ");
        scanf("%d", &ch);
        switch (ch) {
        case 1:
            printf("Temp in %cF is: %.2f\n", 248, ctof());
            break;
        case 2:
            printf("Square root of the number is: %.2f\n", sqr());
            break;
        case 3:
            lucky();
            break;
        case 4:
            printf("Factorial of %d! is: %ld\n", a, fact());
            break;
        case 9:
            exit(1);
        default:
            printf("Invalid choice\n");
        }
    }
}

float ctof() {
    float fah;
    float cel;
    printf("Enter temp in %cC: ", 248);
    scanf("%f", &cel);
    fah = (9 * cel + 160) / 5;
    return (fah);
}

float sqr() {
    float sqr, no;
    printf("Enter the number: ");
    scanf("%f", &no);
    sqr = sqrt(no);
    return (sqr);
}

long int fact() {
    int i;
    long int pro = 1;
    printf("Enter the number: ");
    scanf("%d", &a);
    for (i = 0; (a - i) > 0; i++)
        pro = pro * (a - i);
    return (pro);
}

void lucky() {
    int b, c, i;
    printf("Enter the two numbers: \n");
    scanf("%d%d", &a, &b);
    printf("\n10 Lucky numbers between %d and %d are: \n", a, b);
    for (i = 0; i < 10;) {
        c = rand();
        if ((c > a && c < b) || (c > b && c < a)) {
            printf("%-5d", c);
            i++;
        }
    }
    printf("\n");
}

#include<stdio.h>
#include<stdlib.h>

void threeno();
int sumno(int);
int sumos(int);
int pro(int);
int a, b, c;

void main() {
    int ch, x;
    while (1) {
        printf("\nMENU");
        printf("\n1.Input three numbers");
        printf("\n2.Summation of the numbers\n3.Sum of squares");
        printf("\n4.Product of the three numbers");
        printf("\n5.Exit from program");
        printf("\n\nEnter your choice: ");
        scanf("%d", &ch);
        switch (ch) {
        case 1:
            threeno();
            break;
        case 2:
            printf("Summation of the numbers is: %d\n", sumno(x));
            break;
        case 3:
            printf("Sum of squares is: %d\n", sumos(x));
            break;
        case 4:
            printf("Product of the numbers is: %d\n", pro(x));
            break;
        case 5:
            exit(1);
        default:
            printf("Invalid choice\n");
        }
    }
}

void threeno() {
    printf("Enter the three numbers: \n");
    scanf("%d%d%d", &a, &b, &c);
}

int sumno(int sum) {
    threeno();
    sum = a + b + c;
    return (sum);
}

int sumos(int sum) {
    threeno();
    sum = a * a + b * b + c * c;
    return (sum);
}

int pro(int pro) {
    threeno();
    pro = a * b * c;
    return (pro);
}

/*Find the sum of two matrices*/
#include<stdio.h>

void main() {
    int i, j;
    int A[3][5] = { { 2, 1, 3, 7, 6 }, { 8, 13, 4, 0, 1 }, { 1, 2, 3, 4, 5 } },
        B[3][5] = { { 0, 1, 2, 3, 4 }, { 9, 1, 2, 6, 7 }, { 4, 0, 3, 7, 1 } },
        C[3][5];
    for (i = 0; i < 3; i++)
        for (j = 0; j < 5; j++)
            C[i][j] = A[i][j] + B[i][j];
    printf("\nThe matrix C is:\n");
    for (i = 0; i < 3; i++) {
        for (j = 0; j < 5; j++)
            printf("%3d  ", C[i][j]);
        printf("\n");
    }
}

/*Program to Print Fibonacci terms*/
#include<stdio.h>

void main() {
    int a, b, c, i, n;
    printf("\nEnter the first two numbers: ");
    scanf("%d %d", &a, &b);
    printf("Enter the value of n: ");
    scanf("%d", &n);
    printf("\nThe %d Fibonacci terms are: ", n);
    printf("%d, %d", a, b);
    for (i = 2; i < n; i++) {
        c = a + b;
        a = b;
        b = c;
        printf(", %d", c);
    }
}

/*Check if a phrase is Palindrome*/
#include<stdio.h>
#include<string.h>

void main() {
    char phr[50], phrs[50];
    int i, j;
    printf("\nEnter the phrase: ");
    gets(phr);
    i = strlen(phr);
    for (j = 0; j < i; j++) {
        phrs[j] = phr[i - 1 - j];
    }
    if (strcmpi(phr, phrs) == 0)
        printf("\nIt is a palindrome");
    else
        printf("\nIt is not a palindrome");
}

/*Convert lowercase letters to uppercase*/
#include<stdio.h>
#include<string.h>

void main() {
    char phr[50];
    int i;
    clrscr();
    printf("\nEnter the phrase in small letter:\n");
    gets(phr);
    for (i = 0; i < 50; i++)
        phr[i] = toupper(phr[i]);
    puts(phr);
}

/*Program to reverse array elements*/
#include<stdio.h>

void main() {
    int A[10], i, temp;
    printf("\nEnter the ten numbers:\n");
    for (i = 0; i < 10; i++)
        scanf("%d", &A[i]);
    for (i = 0; i < 5; i++) {
        temp = A[i];
        A[i] = A[9 - i];
        A[9 - i] = temp;
    }
    printf("\nReverse order is:\n");
    for (i = 0; i < 10; i++)
        printf("\n%d", A[i]);
}

/*Program to interchange array elements*/
#include<stdio.h>

void main() {
    int A[10] = { 21, 3, 61, 80, 9, 73, 0, 5, 1, 2 }, i, B[10];
    for (i = 0; i < 10; i += 2) {
        B[i] = A[i + 1];
        B[i + 1] = A[i];
    }
    printf("\nOriginal array is: ");
    for (i = 0; i < 10; i++)
        printf("%d  ", A[i]);
    printf("\nInterchanged array is: ");
    for (i = 0; i < 10; i++)
        printf("%d  ", B[i]);
}

/*C Program to find deviation from average of a given data*/
#include<stdio.h>
#include<math.h>

void main() {
    int temp[7], i, sum = 0, av;
    float dev;
    printf("\nEnter the seven days temperature:\n");
    for (i = 0; i < 7; i++) {
        scanf("%d", &temp[i]);
        sum += temp[i];
    }
    av = sum / 7;
    for (i = 0; i < 7; i++) {
        dev = av - temp[i];
        dev = fabs(dev);
        printf("deviation= %3.1f\n", fabs(dev));
    }
}

/*C Program to print the sum of digits of a number*/
#include<stdio.h>

void main() {
    int n1, sum = 0;
    long int no;
    printf("Enter the number: ");
    scanf("%ld", &no);
    while (no != 0) {
        n1 = no % 10;
        no = no / 10;
        sum = sum + n1;
    }
    printf("\nSum=%d", sum);
}

/*C Program to give a conditional decision*/
#include<stdio.h>

void main() {
    int cnt = 0, a = 0, b = 0, c = 0, age;
    for (cnt = 0; cnt < 15; cnt++) {
        printf("Enter the age: ");
        scanf("%d", &age);
        if (age <= 15)
            a++;
        else if (age <= 17)
            b++;
        else
            c++;
    }
    printf("\nStill a baby= %d", a);
    printf("\nAttending school= %d", b);
    printf("\nAdult life= %d", c);
}