Loop control statements are used to repeat set of statements. They are as follows −
- for loop
- while loop
- do-while loop
for loop
The syntax is as follows −
for (initialization ; condition ; increment / decrement){
body of the loop
}Flow chart
The flow chart for loop is as follows −
Initialization is usually an assignment statement that is used to set the loop control variable.
The condition is a relational expression that determines when the loop will exit.
The increment/decrement part defines how the loop control variable will change each time loop is repeated.
Loop continues to execute as long as the condition is true.
Once the condition is false, program continues with the next statement after for loop.
Example
Following is the C program for loop control statement −
#include<stdio.h>
main( ){
int k;
for (k = 1; k<=5; k++){
printf ("%d",k);
}
}Output
When the above program is executed, it produces the following result −
1 2 3 4 5
while loop
The syntax is as follows −
while (condition){
body of the loop
}Flow chart
The flow chart for while loop is as follows −
- Initialization is done before the loop.
- Loop continues as long as the condition is true.
- Increment and decrement part is done within the loop.
Example
Following is the C program for while loop control statement −
#include<stdio.h>
main( ){
int k;
k = 1;
while (k<=5){
printf ("%d",k);
k++;
}
}Output
When the above program is executed, it produces the following result −
1 2 3 4 5
do-while loop
The syntax is as follows −
Initialization
do{
body of the loop
inc/ dec
} while (condition);Flow chart
The flow chart for do-while loop is as follows −
Example
Following is the C program for do-while loop control statement −
#include<stdio.h>
main( ){
int k;
k = 1;
do{
printf ("%d",k);
k++;
}
while (k <= 5);
}Output
When the above program is executed, it produces the following result −
1 2 3 4 5