需要支持C++17标准。
if(initializer;variable)
switch(initializer;variable)
initiallizer-初始化器
例子:
if用例:
#include<iostream>
#include<cstdlib>
using std::cout;
using std::cin;
using std::endl;
int main() {
cout << "正在生成0~100之间的数" << endl << "请输入你猜测的整数:(你有1次机会)";
auto x{ 0 };
cin >> x;
if (int z = rand() % 100; x > z) {
cout << "你猜大了,正确的数是" << z << endl;
}
else if (x < z) {
cout << "你猜小了,正确的数是" << z << endl;
}
else {
cout << "你猜对了" << endl;
}
}
switch用例:
#include<iostream>
using std::cout;
using std::cin;
using std::endl;
int main() {
cout << "输入课程成绩:";
int score{ 0 };
cin >> score;
cout << "成绩评级:" << endl;
switch (int x = score / 10; x) {
case 10:
case 9:
cout << "A" << endl;
break;
case 8:
cout << "B" << endl;
break;
case 7:
cout << "C" << endl;
break;
case 6:
default:
cout << "D" << endl;
}
}