C++ bitset test()用法及代码示例

bitset::test()是C++ STL中的一个内置函数，用于测试是否设置了给定索引处的位。

用法:

bitset_name.test(index)

参数：该函数仅接受一个强制性参数索引，该索引指定是否设置该位的索引。

返回值：该函数返回一个布尔值。如果设置了给定索引处的位，则返回true，否则返回false。

以下示例程序旨在说明上述函数：

示例1:

// CPP program to illustrate the 
// bitset::test() function 
// when bitset is a string 
#include <bits/stdc++.h> 
using namespace std; 
  
int main() 
{ 
    // Initialization of bitset 
    bitset<4> b1(string("1100")); 
    bitset<6> b2(string("010010")); 
  
    // Function to check if 2nd index bit 
    // is set or not in b1 
    if (b1.test(2)) 
        cout << "Bit at index 2 of 1100 is set\n"; 
    else
        cout << "Bit at index 2 is not set\n"; 
  
    // Function to check if 3nd index bit 
    // is set or not in b2 
    if (b2.test(3)) 
        cout << "Bit at index 3 of 010010 is set\n"; 
    else
        cout << "Bit at index 3 of 010010 is not set\n"; 
  
    return 0; 
}

输出：

Bit at index 2 of 1100 is set
Bit at index 3 of 010010 is not set

示例2:

// CPP program to illustrate the 
// bitset::test() function 
// when the bitset is a number 
#include <bits/stdc++.h> 
using namespace std; 
  
int main() 
{ 
    // Initialization of bitset 
    bitset<4> b1(5); 
    bitset<6> b2(16); 
  
    // Function to check if 2nd index bit 
    // is set or not in b1 
    if (b1.test(2)) 
        cout << "Bit at index 2 of 5 is set\n"; 
    else
        cout << "Bit at index 2 of 5 is not set\n"; 
  
    // Function to check if 3nd index bit 
    // is set or not in b2 
    if (b2.test(3)) 
        cout << "Bit at index 3 of 16 is set\n"; 
    else
        cout << "Bit at index 3 of 16 is not set\n"; 
  
    return 0; 
}

输出：

Bit at index 2 of 5 is set
Bit at index 3 of 16 is not set

相关用法

注：本文由纯净天空筛选整理自gopaldave大神的英文原创作品 bitset test() in C++ STL。非经特殊声明，原始代码版权归原作者所有，本译文未经允许或授权，请勿转载或复制。