do-while loops in C Language:
Do While Loops in C
The do while loop in C is a control flow statement that allows code to be executed repeatedly based on a given boolean condition. The loop will execute the code block once before checking if the condition is true, then it will repeat the loop as long as the condition is true.
<![CDATA[do {
// statements
} while (condition);]]>
Basic Do While Loop
A basic do while loop executes the statements at least once before checking the condition.
<![CDATA[#include <stdio.h>
int main() {
int i = 0;
do {
printf("i = %d\n", i);
i++;
} while (i < 5);
return 0;
}]]>
Do While Loop with Multiple Conditions
You can use logical operators to create more complex conditions in a do while loop.
<![CDATA[#include <stdio.h>
int main() {
int i = 0, j = 5;
do {
printf("i = %d, j = %d\n", i, j);
i++;
j--;
} while (i < j && j > 0);
return 0;
}]]>
Infinite Do While Loop
A do while loop can run indefinitely if the condition is always true.
<![CDATA[#include <stdio.h>
int main() {
do {
printf("This loop will run forever.\n");
break; // Remove this break statement to see the infinite loop
} while (1);
return 0;
}]]>
Nesting of Do While Loops
You can nest do while loops within each other to perform more complex iterations.
<![CDATA[#include <stdio.h>
int main() {
int i = 1, j;
do {
j = 1;
do {
printf("i = %d, j = %d\n", i, j);
j++;
} while (j <= 3);
i++;
} while (i <= 3);
return 0;
}]]>
Examples
Here are some additional examples demonstrating the usage of do while loops in C:
Example: Summing Numbers
<![CDATA[#include <stdio.h>
int main() {
int sum = 0, i = 1;
do {
sum += i;
i++;
} while (i <= 10);
printf("Sum of first 10 natural numbers is %d\n", sum);
return 0;
}]]>
Example: Finding the Length of a String
<![CDATA[#include <stdio.h>
int main() {
char str[] = "Hello, world!";
int i = 0;
do {
i++;
} while (str[i] != '\0');
printf("Length of the string is %d\n", i);
return 0;
}]]>
Example: Matrix Multiplication
<![CDATA[#include <stdio.h>
int main() {
int a[2][2] = {{1, 2}, {3, 4}};
int b[2][2] = {{2, 0}, {1, 2}};
int c[2][2] = {0};
int i = 0, j, k;
do {
j = 0;
do {
k = 0;
do {
c[i][j] += a[i][k] * b[k][j];
k++;
} while (k < 2);
j++;
} while (j < 2);
i++;
} while (i < 2);
for (i = 0; i < 2; i++) {
for (j = 0; j < 2; j++) {
printf("%d ", c[i][j]);
}
printf("\n");
}
return 0;
}]]>