Control statements determine the flow of execution of a C++ program. They decide which statement executes, how many times, and when.
Types of Statements in C++
1. Declaration Statements
Used to declare variables.
int a;
float marks;
2. Assignment Statements
Used to assign values to variables.
a = 10;
marks = 85.5;
3. Input / Output Statements
Used to take input and display output.
cin >> a;
cout << a;
4. Control Statements
Control the flow of program execution.
A. Selection (Decision) Statements
Used for decision making.
1. if Statement
if (a > 0) {
cout << "Positive";
}
2. if-else Statement
if (a % 2 == 0)
cout << "Even";
else
cout << "Odd";
3. else-if Ladder
if (marks >= 90)
cout << "Grade A";
else if (marks >= 75)
cout << "Grade B";
else
cout << "Grade C";
4. switch Statement
switch(choice) {
case 1: cout << "One";
break;
case 2: cout << "Two";
break;
default: cout << "Invalid";
}
B. Iteration (Looping) Statements
Used to repeat statements.
1. for Loop
for(int i = 1; i <= 5; i++) {
cout << i;
}
2. while Loop
int i = 1;
while(i <= 5) {
cout << i;
i++;
}
3. do-while Loop
int i = 1;
do {
cout << i;
i++;
} while(i <= 5);
C. Jump Statements
Used to transfer control.
Statement Use
break Exit loop or switch
continue Skip current iteration
goto Jump to labeled statement
return Exit function
Example:
if (a < 0)
return 0;
5. Expression Statements
Statements containing expressions.
a = b + c;
x++;
6. Compound (Block) Statements
Group of statements enclosed in { }.
{
int x = 5;
cout << x;
}
Breaking Control Statements in C++
Breaking control statements are used to interrupt the normal flow of execution in loops or switch statements, or to exit a function.
1. break Statement
Terminates the nearest loop or switch
Control moves to the statement after the loop/switch
Example (Loop)
for(int i = 1; i <= 5; i++) {
if(i == 3)
break;
cout << i << " ";
}
// Output: 1 2
Example (Switch)
switch(ch) {
case 'A': cout << "Apple";
break;
case 'B': cout << "Ball";
}
2. continue Statement
Skips the current iteration
Loop continues with the next iteration
Example
for(int i = 1; i <= 5; i++) {
if(i == 3)
continue;
cout << i << " ";
}
// Output: 1 2 4 5
3. goto Statement
Transfers control to a labeled statement
Generally not recommended (reduces readability)
Example
int i = 1;
start:
cout << i << " ";
i++;
if(i <= 5)
goto start;
4. return Statement
Exits from a function
Can return a value
Example
int sum(int a, int b)
{
return a + b;
}
Difference Between break and continue
Feature break continue
Exits loop Yes No
Skips iteration No Yes
Used in switch Yes No
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