![Declaring Arrays
¤ Declaration examples:
int[] counts;
double[] scores;
String[] studentNames;
¤Syntax:
Data type Array name [constant]](https://image.slidesharecdn.com/1dimansionalarray-160914073436/85/One-Dimentional-Array-4-320.jpg)
![Array Allocation
Arrays are allocated using the Java new operator
The syntax is:
new type[size];
Examples:
counts = new int[10];
scores = new double[15];
studentNames = new String[10];](https://image.slidesharecdn.com/1dimansionalarray-160914073436/85/One-Dimentional-Array-5-320.jpg)
![Array Initialization
• Arrays can be initialized by giving a list of their elements
• If your list contains n elements the subscripts will range
from 0 to n – 1
• Do not need to allocate the array explicitly after it is
initialized
• Example:
int [] primes = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29};](https://image.slidesharecdn.com/1dimansionalarray-160914073436/85/One-Dimentional-Array-7-320.jpg)
![Arrays of Objects
•Arrays of objects are declared in the same manner
as arrays of primitive variables
•Assuming that a class Student was declared
elsewhere a client application could declare and
allocate an array of 10 students using
Student[ ] students;
students = new Student[10];](https://image.slidesharecdn.com/1dimansionalarray-160914073436/85/One-Dimentional-Array-8-320.jpg)
![#include<stdio.h>
#include<string.h>
int main()
{
char s1[80],s2[80];
gets (s1);
gets (s2);
puts(s1);
puts(s2);
printf("length:%d %dn",strlen(s1),strlen(s2));
return 0;
}
Example of 1D ARRAY](https://image.slidesharecdn.com/1dimansionalarray-160914073436/85/One-Dimentional-Array-9-320.jpg)
![#include <stdio.h>
int main()
{
int i, n;
float
a[100],sum=0,sum_pos=0,sum_neg=0,avg;
printf("enter the value:");
scanf("%d",&n);
for(i=0;i<n; i++)
{ scanf("%f",&a[i]);
}
for(i=0;i<n; i++)
{
if(a[i]>0)
sum_pos=sum_pos+a[i];
}
for(i=0;i<n; i++)
{
if(a[i]<0)
sum_neg=sum_neg+a[i];
}
sum=sum_pos+sum_neg;
avg=sum/n;
printf("%fn",sum);
printf("%fn",avg);
return 0;
}
Example of 1D ARRAY](https://image.slidesharecdn.com/1dimansionalarray-160914073436/85/One-Dimentional-Array-10-320.jpg)
One Dimentional Array
- 3. One Dimensional Array ♣Structured collection of components. ♣Structure given a single name. ♣Individual elements accessed by index indicating relative position in collection. ♣Type of elements stored in an array can be “just about” anything. ♣Index of an array must be an integer.
- 4. Declaring Arrays ¤ Declaration examples: int[] counts; double[] scores; String[] studentNames; ¤Syntax: Data type Array name [constant]
- 5. Array Allocation Arrays are allocated using the Java new operator The syntax is: new type[size]; Examples: counts = new int[10]; scores = new double[15]; studentNames = new String[10];
- 6. Array Organization counts Each box is an int variable The numbers on top are each variable’s subscript or index An array of size 10 has subscripts 0 to 9 0 1 2 3 4 5 6 7 8 9
- 7. Array Initialization • Arrays can be initialized by giving a list of their elements • If your list contains n elements the subscripts will range from 0 to n – 1 • Do not need to allocate the array explicitly after it is initialized • Example: int [] primes = {2, 3, 5, 7, 11, 13, 17, 19, 23, 29};
- 8. Arrays of Objects •Arrays of objects are declared in the same manner as arrays of primitive variables •Assuming that a class Student was declared elsewhere a client application could declare and allocate an array of 10 students using Student[ ] students; students = new Student[10];
- 9. #include<stdio.h> #include<string.h> int main() { char s1[80],s2[80]; gets (s1); gets (s2); puts(s1); puts(s2); printf("length:%d %dn",strlen(s1),strlen(s2)); return 0; } Example of 1D ARRAY
- 10. #include <stdio.h> int main() { int i, n; float a[100],sum=0,sum_pos=0,sum_neg=0,avg; printf("enter the value:"); scanf("%d",&n); for(i=0;i<n; i++) { scanf("%f",&a[i]); } for(i=0;i<n; i++) { if(a[i]>0) sum_pos=sum_pos+a[i]; } for(i=0;i<n; i++) { if(a[i]<0) sum_neg=sum_neg+a[i]; } sum=sum_pos+sum_neg; avg=sum/n; printf("%fn",sum); printf("%fn",avg); return 0; } Example of 1D ARRAY
- 11. Thank you