int len = sizeof(array) / sizeof(int);

这行代码用于计算数组array的长度。在C语言中，可以使用`sizeof`操作符来计算数组或变量在内存中占用的字节数。`sizeof(array)`表示整个数组array所占用的字节数，而`sizeof(int)`表示int类型的字节数。

因为数组array中每个元素的类型都是int，所以将整个数组的字节数除以int类型的字节数，就可以得到数组的长度。

这样计算数组长度的好处是，可以避免手动指定数组长度，提高代码的可维护性和灵活性。无论数组的大小如何改变，都可以正确计算出数组的长度。

相关问题

int len=sizeof(a)/sizeof(a[0]);

This line of code calculates the length of an array "a" by dividing the total size of the array by the size of its first element.

The "sizeof" operator in C++ returns the size in bytes of a variable or data type. In this case, it is used to get the total size of the array "a" in bytes.

The "/ sizeof(a[0])" part of the line of code divides the total size of the array by the size of its first element, which gives the number of elements in the array.

The variable "len" is then assigned the value of the number of elements in the array, which can be used in subsequent code to loop through the array or perform other operations.

int a[]={-2,2,-3,4,-1,2,1,-5,3}; int len=sizeof(a)/sizeof(a[0]);

This code declares an integer array `a` with 9 elements and initializes it with the values -2, 2, -3, 4, -1, 2, 1, -5, and 3.

The variable `len` is then assigned the value of the length of the array `a`, which is determined by dividing the size of the whole array (in bytes) by the size of one element (in bytes). This gives us the number of elements in the array.

Assuming this code is written in C or C++, the types of `a` and `len` are automatically inferred as `int[]` and `int`, respectively.