C++ if-else基础教程文档
收录于 2023-04-20 00:10:05 · بالعربية · English · Español · हिंदीName · 日本語 · Русский язык · 中文繁體
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:
It is even number
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:
It is odd number
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