The switch case in cpp is a replacement for the lengthy if statements that are used to compare a variable to several integral values. These statements have multiple branches. The switch statements enable any value to alter the execution's direction. They also allow for the optimum distribution ...
对于一个局部变量,它的作用域为它所定义的地方到它所在的语句块结束为止,那么对于变量b,它所在的最小语句块为switch{}块,那么也就说在case 0后面的部分,变量b都是可见的(注意在case 0之前变量b是无法访问的)。考虑这样一种情况,当a的值为1,那么程序就跳到case 1执行,此时b虽然可以访问,但是跳过了它的初始...
一个switch语句可以包含任意数量的case标签,每个case标签中可执行若干条语句,通常以break语句结束。default标签为可选项,至多包含一个,用于处理case标签未列举的值。 switch(expression) {caseconstant_expression_1 :// statement_1break;caseconstant_expression_2 :// statement_2break;/* ... */default:// state...
Switch case statement is used when we have multiple conditions and we need to perform different action based on the condition. When we have multiple conditions and we need to execute a block of statements when a particular condition is satisfied. In such case either we can use lengthyif..else...
cout << " === Program to demonstrate the concept of Switch Case with break statement, in CPP === \n\n"; //variable to store the operation to be performed char operation; //variable to store the operands int n1, n2, result; cout <...
C++ 标准中的switch是不能够实现字符串的 case 匹配的,但是往往我们也有这个需求,来实现一下。 我们需要实现的结果如下: 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 switch("123"){ case"123":{ // ... break; } case"456":{ // ... ...
C++中的switch case语句。 switch case语句是一种控制结构,允许程序根据变量的值执行不同的代码。它类似于if-else语句,但对于处理多个情况更有效。 语法。 switch case语句的语法如下: cpp. switch (变量) {。 case值1: //如果变量等于值1,则执行的代码。 break; case值2: //如果变量等于值2,则执行的代码...
case 15...175: //ERROR cout << "B"; break; default: cout << "D"; break; } } Edit & run on cpp.shNov 13, 2019 at 4:22am lastchance (6980) You can't use a range (in c++). If they had been equal intervals you might have been able to linearly transform, together ...
case false: if ( file_name.empty()) //错误:file_name不在作用域内 break; 表述多情况时不能用逗号 switch(i){ case 1,2,3,4: //错误写法 cout<<"i = 1,2,3,4"<<endl; break; default : cout<<"in default"<<endl; break;
一提到switch,难免出来许多case,代码长而不爽,工程效率也大大下降。举例说明:一个学生管理系统,定义各种菜单栏,用户在控制台进行输入,由输入自主选择菜单。 1. 菜单栏声明如下,具体实现略去 class Menu { public: void Welcome(); v...