//Array, Loop, and C string


#include <stdio.h> 

void iniArray();
void evenNums();
void oddNums();
void copyArray();
void Cstring();

int main()
{
  //iniArray();
  //evenNums();
  //oddNums();
  //copyArray();
  Cstring();

  return 0;
}

void iniArray(){
  printf("\nThis function ask values of array x one by one from user.\n");
  const int N = 5;
  //declare an integer array x of N elements
  
  int x[N];

  int len = sizeof(x)/sizeof(x[0]);
   
  //ask user to enter the values of elements

  for (int i = 0; i < len; i++) {
    printf("Enter element %d: ", i + 1);
    scanf("%d", &x[i]);
  }

  //display all the values of x
  printf("Array x[%d] has values: {", len);
  for (int i = 0; i < len-1; i++) {
    printf("%d, ", x[i]);
  }
  printf("%d}\n", x[len-1]);
}

void evenNums(){
  printf("\nThe function will store 10 even numbers starting from 0 to array A. Print the array\n");
  //declare variables

  int A[10];

  for (int i = 0; i < 10; i++) {
    A[i] = i * 2 + 4;
  }

  for (int i = 0; i < 10; i++) {
    printf("%d ", A[i]);
  }
  printf("\n");
}
void oddNums(){
  printf("\nThe function will store 10 odd numbers starting from 1 to array A. Print the array\n");
  //declare variables
  int A[10];

  for (int i = 0; i < 10; i++) {
    A[i] = i * 2 + 1;
  }

  for (int i = 0; i < 10; i++) {
    printf("%d ", A[i]);
  }
  printf("\n");
}
void copyArray(){
    printf("\nThis function copy element of array A to array B.\n");
    
  int A[] = {2, 4, 6, 8}; // A is an integer array of length 4
  int B[3]; 
  int i; // loop index
  //copy and print B
  int lenB = sizeof(B)/sizeof(B[0]);
  int lenA = sizeof(A)/sizeof(A[0]);

  for (int i = lenA - lenB; i < lenA; i++) {
    B[i] = A[i];
    printf("%d ", B[i]);
  }
  printf("\n");
  //print A
  for (int i = 0; i < lenA; i++) {
    printf("%d ", A[i]);
  }
  printf("\n");
}

void Cstring(){
  printf("\nThis function is for you to learn C string.\n");
  //declare an array of charaters 
  char x[] = {'g', 'a', 'r', 'r', 'e', 't', 't', '\0'};
  printf("x = %s, size = %lu\n", x, sizeof(x));

  //declare a C string y using " "
  char y[] = "Hello There";
  printf("y = %s, size = %lu\n", y, sizeof(y));
  //declare a C string z using { }, '\0' indicate the end of string 
  char z[] = {'A', 'B', 'C', '\0'};
  printf("z = %s, size = %lu\n", z, sizeof(z));


  for (int i = 0; x[i]; i++) {
    printf("%c\n", x[i]);
  }
}