Write a Program to Sort an Array using Selection Sort in C with a practical example of for loop, while loop, and functions. This program uses Nested For Loop to sort the array elements using selection sort.
// using nested for loop
#include <stdio.h>
int main()
{
int a[100], number, i, j, temp;
printf("\n Please Enter the total Number of Elements : ");
scanf("%d", &number);
printf("\n Please Enter the Array Elements : ");
for(i = 0; i < number; i++)
scanf("%d", &a[i]);
for(i = 0; i < number; i++) {
for(j = i + 1; j < number; j++) {
if(a[i] > a[j]) {
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
}
}
printf("\n Selection Sort Result : ");
for(i = 0; i < number; i++) {
printf(" %d \t", a[i]);
}
printf("\n");
return 0;
}
Here, in this C selection sort program, the For Loop will make sure that the number is between 1 and maximum size – 1.
First For Loop – First Iteration: for(i = 0; 0 < 4; 0++)
The condition is True so, it will enter into the second for loop.
Second For Loop in C – First Iteration: for(j = 1; 1 < 4; 1++) – This condition is True
if(a[0] > a[1]) => (10 > 9) – This condition is True
temp = 10
a[i] = a[j] => a[0] = 9
a[j] = temp => a[1] = 10
Now the array will be 9 10 0 11.
Second For Loop – Second Iteration: for(j = 2; 2 < 4; 2++) – True
if(a[0] > a[2]) => (9 > 0) – Condition is True
temp = a[0] => temp = 9
a[0] = a[2] => a[0] = 0
a[2] = temp => a[2] = 9
Now the array will be 0 10 9 11.
Do the same for the remaining Iterations of the second for loop. Next, repeat the same with the first C Programming for loop.
C Program for Selection Sort using for loop
In this selection sort program, we used a slightly different approach to demonstrate this.
#include <stdio.h>
int main()
{
int a[100], num, min, i, j, temp;
printf("\n Please Enter the total Elements : ");
scanf("%d", &num);
printf("\n Please Enter the Array Elements : ");
for(i = 0; i < num; i++)
scanf("%d", &a[i]);
for(i = 0; i < num - 1; i++) {
min = i;
for(j = i + 1; j < num; j++) {
if(a[min] > a[j]) {
min = j;
}
}
if(min != i)
{
temp = a[i];
a[i] = a[min];
a[min] = temp;
}
}
printf("\n Result : ");
for(i = 0; i < num; i++) {
printf(" %d \t", a[i]);
}
printf("\n");
return 0;
}
Please Enter the total Elements : 5
Please Enter the Array Elements : 10 2 19 0 10
Result : 0 2 10 10 19 Selection Sort Program using While Loop
In this C program, we replaced the for loop with the C programming While Loop.
#include <stdio.h>
int main()
{
int a[100], val, i, j, temp;
printf("\n Please Enter the total No. of Elements : ");
scanf("%d", &val);
printf("\n Please Enter the Array Elements : ");
for(i = 0; i < val; i++)
scanf("%d", &a[i]);
i = 0;
while( i < val) {
j = i + 1;
while( j < val) {
if(a[i] > a[j]) {
temp = a[i];
a[i] = a[j];
a[j] = temp;
}
j++;
}
i++;
}
printf("\n Result : ");
for(i = 0; i < val; i++) {
printf(" %d \t", a[i]);
}
printf("\n");
return 0;
}
Please Enter the total No. of Elements : 7
Please Enter the Array Elements : 20 0 25 19 4 22 16
Result : 0 4 16 19 20 22 25 C Selection Sort Program using Functions
This program uses Functions to separate the logic and Pointers to swap and rearrange the array elements by using this selection sort. Please check out the Pointers in C article and the C Program to swap two numbers.
#include <stdio.h>
void Swap(int *x, int *y) {
int Temp;
Temp = *x;
*x = *y;
*y = Temp;
}
void selFunc(int a[], int number) {
int i, j;
for(i = 0; i < number; i++) {
for(j = i + 1; j < number; j++) {
if(a[i] > a[j]) {
Swap(&a[i], &a[j]);
}
}
}
}
int main()
{
int a[100], number, i;
printf("\n Please Enter the total Number of Elements : ");
scanf("%d", &number);
printf("\n Please Enter the Array Elements : ");
for(i = 0; i < number; i++)
scanf("%d", &a[i]);
selFuc(a, number);
printf("\n Result : ");
for(i = 0; i < number; i++) {
printf(" %d \t", a[i]);
}
printf("\n");
return 0;
}
Please Enter the total Number of Elements : 6
Please Enter the Array Elements : 12 3 0 22 19 -8
Result : -8 0 3 12 19 22 Also Read