The count() function in C The count() function counts the number of occurrences of a specific element in a container. Syntax: size_t count(const Type& element); Parameters: element, the element to be found. Return value: the number of times the element appears. Usage: Take the element to be counted as a parameter, and the function returns its number of occurrences.
The count() function in C
In C, the count() function is a container operation function , used to count the number of occurrences of a specific element in a container.
Syntax:
size_t count(const Type& element);
Parameters:
-
element
: The element to be found .
Return value:
- The number of times the element appears in the container.
Instructions:
To use the count() function, simply pass the element whose occurrence you want to count as a parameter to the function. . This function returns the number of occurrences of the element in the container.
Example:
#include <vector> int main() { // 创建一个包含整数的 vector std::vector<int> numbers = {1, 2, 3, 4, 5, 1, 2, 3}; // 计算 vector 中数字 3 出现的次数 int count_of_3 = std::count(numbers.begin(), numbers.end(), 3); // 打印数字 3 出现的次数 std::cout <p><strong>Output:</strong></p> <pre class="brush:php;toolbar:false">数字 3 出现的次数:2
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