C++ if-else
在C++编程中，if语句用于测试条件。 C++中有多种类型的if语句。
if语句
if-else语句
嵌套if语句
if-else-if语句
C++ IF语句
C++ if语句测试条件。条件为真时执行。
if(condition){
//code to be executed
}
如果是C++示例
#include <iostream>
using namespace std;
int main () {
int num = 10;
if (num % 2 == 0)
{
cout<<"It is even number";
}
return 0;
}
输出:
C++ IF-else语句
C++ if-else语句也测试条件。如果条件为true则执行block，否则执行block。
if(condition){
//code if condition is true
}else{
//code if condition is false
}
C++ If-else示例
#include <iostream>
using namespace std;
int main () {
int num = 11;
if (num % 2 == 0)
{
cout<<"It is even number";
}
else
{
cout<<"It is odd number";
}
return 0;
}
输出:
C++ If-else示例: 来自用户的输入
#include <iostream>
using namespace std;
int main () {
int num;
cout<<"Enter a Number: ";
cin>>num;
if (num % 2 == 0)
{
cout<<"It is even number"<<endl;
}
else
{
cout<<"It is odd number"<<endl;
}
return 0;
}
输出:
Enter a number:11
It is odd number
输出:
Enter a number:12
It is even number
C++ IF-else-if阶梯语句
C++ if-else-if阶梯语句从多个语句中执行一个条件。
if(condition1){
//code to be executed if condition1 is true
}else if(condition2){
//code to be executed if condition2 is true
}
else if(condition3){
//code to be executed if condition3 is true
}
...
else{
//code to be executed if all the conditions are false
}
C++ If else-if示例
#include <iostream>
using namespace std;
int main () {
int num;
cout<<"Enter a number to check grade:";
cin>>num;
if (num <0 || num >100)
{
cout<<"wrong number";
}
else if(num >= 0 && num < 50){
cout<<"Fail";
}
else if (num >= 50 && num < 60)
{
cout<<"D Grade";
}
else if (num >= 60 && num < 70)
{
cout<<"C Grade";
}
else if (num >= 70 && num < 80)
{
cout<<"B Grade";
}
else if (num >= 80 && num < 90)
{
cout<<"A Grade";
}
else if (num >= 90 && num <= 100)
{
cout<<"A+ Grade";
}
}
输出:
Enter a number to check grade:66
C Grade
输出:
Enter a number to check grade:-2
wrong number
