Array

An Array is a group of elements of same type sharing same name and stored in consecutive memory locations.
Where loop can be any loop i.e. while loop, for loop or do-while loop.Whenever we want to store multiple values of same type then an array can be used.

Defining an Array

An Array can be created by specifying data type, array name and its size.

Syntax:

datatype arrayname[size];

For eg: int a[10];

Accessing Array Elements

Elements of an array can be accessed by using subscript operator [ ].

Syntax:

arrayname[index]

For eg:a[0] a[1] a[2] etc.

Note: Index No. begins with zero.

Array Initialization

While defining an array we can directly store values into it.

Syntax:

datatype arrayname[size]={values…};

For eg:

int a[5]={32,12,55,2,34};
int a[]={32,12,55,2,34};
int a[5]={32,12,55};
int a[5]={32,12,55,2,34,54,22,6}; //ERROR

Note: If array is initialize then size of array is optional

#Write a program to display all the elements of array.

  #include<stdio.h>
  main()
  {
    int arr[5]={2,5,3,4,1};
    for(int i=0;i<=4;i++)
        printf("%d ",arr[i]);
  }

2 5 3 4 1

#Write a program to display all the elements of array size 10.

  #include<stdio.h>
  main()
  {
    int a[10]={5,2,4,8,10,12,3,15,3,6};
    for(int i=0;i<=9;i++)
        printf("%d ",a[i]);
  }

5 2 4 8 10 12 3 15 3 6

#Write a program to find sum of all elements in array.

  #include<stdio.h>
  main()
  {
    int s=0;
    int a[10]={5,2,4,8,10,12,3,15,3,6};
    for(int i=0;i<=9;i++)
        s=s+a[i];
    printf("Sum is %d ",s);
 }

Sum is 68

#Write a program to find sum of all even numbers in array.

  #include<stdio.h>
  main()
  {
    int s=0;
    int a[10]={5,2,4,8,10,12,3,15,3,6};
    for(int i=0;i<=9;i++)
    {
        if(a[i]%2==0)
            s=s+a[i];
    }
    printf("Sum of even numbers is %d ",s);
  }

Sum of even numbers is 42

#Write a program to find sum of all odd numbers in array.

  #include<stdio.h>
  main()
  {
    int s=0;
    int a[10]={5,2,4,8,10,12,3,15,3,6};
    for(int i=0;i<=9;i++)
    {
        if(a[i]%2!=0)
            s=s+a[i];
    }
    printf("Sum of odd number is %d ",s);
  }

Sum of odd number is 26

#Write a program to read an array of size 10 and display it.

  #include<stdio.h>
  main()
  {
    int a[10];
    int s=0;
    printf("Enter 10 no: \n");
    for(int i=0;i<10;i++)
        scanf("%d",&a[i]);
    printf("Array values are:\n")
    for(int i=0;i<10;i++)
        printf("%d ",a[i]);
  }

Enter 10 nos: 
2 3 4 5 6 1 9 8 7 0
Array values are:
2 3 4 5 6 1 9 8 7 0

#Write a program to read an array of size 10 and find the sum all elements.

  #include<stdio.h>
  main()
  {
    int a[10],s=0;
    printf("Enter 10 nos:");
    for(int i=0;i<10;i++)
    {
        scanf("%d",&a[i]);
        s=s+a[i];
    }
    printf("Sum is %d",s);
  }

Enter 10 nos: 
2 3 5 6 4 6 5 2 10 8
Sum is 51

#Write a program to read an array of size 10 and find the sum all even number.

  #include<stdio.h>
  main()
  {
    int a[10];
    int s=0;
    printf("Enter a number: \n");
    for(int i=0;i<10;i++)
    {
        scanf("%d",&a[i]);
        if(a[i]%2==0)
            s=s+a[i];
    }
    printf("Sum of all even no is %d",s);
  }

Enter 10 number
10 21 3 8 15 14 12 6 7 15
Sum of all even no is 50

#Write a program to read an array of size 10 and find the sum all odd number.

  #include<stdio.h>
  main()
  {
    int a[10],s=0;
    printf("Enter 10 numbers: \n");
    for(int i=0;i<10;i++)
    {
        scanf("%d",&a[i]);
        if(a[i]%2!=0)
            s=s+a[i];
    }
    printf("Sum of all odd no is %d",s);
  }

Enter 10 numbers:
1 2 3 4 5 6 7 8 9 0
Sum of all odd no is 25

#Write a program to read temperature values for 7 days of a week and find average temperature of that week.

  #include<stdio.h>
  main()
  {
    int a[7],s=0,i;
    float Avg;
    printf("Enter temperature 7 days\n");
    for(i=0;i<=6;i++)
    {
        scanf("%d",&a[i]);
        s=s+a[i];
        Avg=s/7.0;
    }
    printf("Average temperature is %f",Avg);
  }

Enter temperature 7 days
21 23 24 25 26 21 20
Average temperature is 22.8571

#Write a program to read 10 nos in an int array and check if sum of first 5 elements is equals to sum of last 5 elements.

  #include<stdio.h>
  main()
  {
    int a[10],s1=0,s2=0,i;
    printf("Enter 10 number:\n");
    for(i=0;i<=9;i++)
        scanf("%d",&a[i]);
    for(i=0;i<=4;i++)
        s1=s1+a[i];
    for(i=5;i<=9;i++)
        s2=s2+a[i];
    if(s1==s2)
        printf("sum is equal");
    else
        printf("sum is not equal");
  }

Enter 10 number: 
8 5 6 3 7 4 5 9 6 4
sum is not equal

#Write a program to read 10 nos in an int array and count all negative nos. in that array.

  #include<stdio.h>
  main()
  {
    int a[10],c=0,i;
    printf("Enter 10 numbers:\n");
    for(i=0;i<=9;i++)
    {
        scanf("%d",&a[i]);
        if(a[i]<0)
            c=c+1;
    }
    printf("Negative Number are %d",c);
  }

Enter 10 numbers:
8 5 -6 3 7 -4 5 -9 6 4
Negative Number are 3

#Write a program to read 10 numbers in an int array and count all even numbers in that array.

  #include<stdio.h>
  main()
  {
    int a[10],c=0,i;
    printf("Enter 10 numbers:\n");
    for(i=0;i<=9;i++)
    {
        scanf("%d",&a[i]);
        if(a[i]%2==0)
            c=c+1;
    }
    printf("Even Number are %d",c);
  }

Enter 10 numbers:
8 5 6 3 7 4 5 9 6 4
Even Number are 5

#Write a program to read 10 numbers in an int array and count all non-zero numbers in that array.

  #include<stdio.h>
  main()
  {
    int a[10],c=0,i;
    printf("Enter 10 numbers:\n");
    for(i=0;i<=9;i++)
    {
        scanf("%d",&a[i]);
        if(a[i]!=0)
            c=c+1;
    }
    printf("Non zero number are %d",c);
  }

Enter 10 numbers:
8 0 6 3 7 0 5 9 0 4
Non zero number are 7

#Write a program to read 10 numbers in an int array and find greatest number in that array.

  #include<stdio.h>
  main()
  {
    int a[10],G,i;
    printf("Enter 10 numbers:\n");
    for(i=0;i<=9;i++)
        scanf("%d",&a[i]);
    G=a[0];
    for(i=1;i<=9;i++)
    {
        if(a[i]>G)
            G=a[i];
    }
    printf("Greatest number is %d",G);
  }

Enter 10 numbers:
3 5 4 2 10 6 12 7 9 8
Greatest number is 12

CCITcoder

Introduction to C

DataType and Operation

Conditional statements

Iterative statements

Functions

Array

Pointers

Structures

File I/O

Graphics

Additional Features

Introduction to C

DataType and Operation

Conditional statements

Iterative statements

Functions

Array

Pointers

Structures

File I/O

Graphics

Additional Features

Array

Array

Defining an Array

Accessing Array Elements

Array Initialization