用来自动获取变量的类型 for (auto &x : my_array) { x *= 2; cout << x << endl; ...
意思是将 counts 容器中的每一个元素从前往后枚举出来，并用 count 来表示，类似于Java中的 for each 语句，举个栗子：include<iostream>#include<vector>using namespace std;int main() {int a[] = { 1,2,3,5,2,0 };vector<int>counts(a,a+6);for (auto count : counts)cout<< coun...
使用auto声明的变量必须要给初始值,而这里的语法没有给初始值。Range-Based for loop应该是一种语法糖,实际上编译器应该是当成普通的for循环来处理的。 从cppreference(https://en.cppreference.com/w/cpp/language/range-for)上可以得到印证。 Range-Based for loop的一般形式(省略了不相关的部分)实际上等价于...
public: Iter(const IntVector* p_vec, int pos) : _pos(pos), _p_vec(p_vec){} // these three methods form the basis of an iterator for use with a range-based for loop bool operator!=(const Iter& other) const { return _pos != other._pos; } // this method must be defined af...
使用auto声明的变量必须要给初始值,而这里的语法没有给初始值。Range-Based for loop应该是一种语法糖,实际上编译器应该是当成普通的for循环来处理的。 从cppreference(https://en.cppreference.com/w/cpp/language/range-for)上可以得到印证。 Range-Based for loop的一般形式(省略了不相关的部分)实际上等价于...
1. DO UNTIL Loop 2. DO WHILE Loop 3. FOR Loop 1. DO UNTIL Loop The DO UNTIL Loop is used to repeat a block of code indefinitely, until the specified condition is set to True. The condition can either be checked at the beginning or at the end of the Loop. The DO UNTIL … LOOP...
// range-based-for.cpp// compile by using: cl /EHsc /nologo /W4#include<iostream>#include<vector>usingnamespacestd;intmain(){// Basic 10-element integer array.intx[10] = {1,2,3,4,5,6,7,8,9,10};// Range-based for loop to iterate through the array.for(inty : x ) {// ...
1. for ( range_declaration : range_expression) loop_statement 1. “等价于” 1. { 2. auto && __range = range_expression ; 3. auto __begin = begin_expr(__range); 4. auto __end = end_expr(__range); 5. for (;__begin != __end; ++__begin) { ...
for(auto ch : MyClass().getText()) { cout<<ch; } 结果什么都不会输出,程序直接退出。要理解为什么会出现这种行为,要先知道基于范围的for循环是怎么定义的。 基于范围的for循环定义 在C++11标准中,它有以下的格式 1 attr(optional)for( range_declaration : range_expression ) loop_statement ...
In this example, we’ll use a C++ for loop to calculate the factorial of a given number step by step.Code Example:#include <iostream> using namespace std; int main() { int n, factorial = 1; cout << "Enter a number: "; cin >> n; for (int i = 1; i <= n; i++) { ...