C++ Programming Code Examples
C++ > If Else and Switch Case Code Examples
if-else-if statement is used when we need to check multiple conditions.
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/* if-else-if statement is used when we need to check multiple conditions.
In this control structure we have only one "if" and one "else", however we can have multiple "else if" blocks. This is how it looks: */
if(condition_1) {
/*if condition_1 is true execute this*/
statement(s);
}
else if(condition_2) {
/* execute this if condition_1 is not met and
* condition_2 is met
*/
statement(s);
}
else if(condition_3) {
/* execute this if condition_1 & condition_2 are
* not met and condition_3 is met
*/
statement(s);
}
.
.
.
else {
/* if none of the condition is true
* then these statements gets executed
*/
statement(s);
}
/* Example of if-else-if */
#include <iostream>
using namespace std;
int main(){
int num;
cout<<"Enter an integer number between 1 & 99999: ";
cin>>num;
if(num <100 && num>=1) {
cout<<"Its a two digit number";
}
else if(num <1000 && num>=100) {
cout<<"Its a three digit number";
}
else if(num <10000 && num>=1000) {
cout<<"Its a four digit number";
}
else if(num <100000 && num>=10000) {
cout<<"Its a five digit number";
}
else {
cout<<"number is not between 1 & 99999";
}
return 0;
}
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The if...else statement executes two different codes depending upon whether the test expression is true or false. Sometimes, a choice has to be made from more than 2 possibilities. The if...else ladder allows you to check between multiple test expressions and execute different statements. In C/C++ if-else-if ladder helps user decide from among multiple options. The C/C++ if statements are executed from the top down. As soon as one of the conditions controlling the if is true, the statement associated with that if is executed, and the rest of the C else-if ladder is bypassed. If none of the conditions is true, then the final else statement will be executed.
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In computer programming, we use the if statement to run a block code only when a certain condition is met. An if statement can be followed by an optional else statement, which executes when the boolean expression is false. There are three forms of if...else statements in C++: • if statement, • if...else statement, • if...else if...else statement, The if statement evaluates the condition inside the parentheses ( ). If the condition evaluates to true, the code inside the body of if is executed. If the condition evaluates to false, the code inside the body of if is skipped.
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