Pass cursor to function in C ++

C ++ allows you to pass a pointer to a function. To do this, you simply need to declare the function parameter as in a pointer type.

In the simple example below, we pass an unsigned long pointer to a function and change the value inside the function, which reflects back while calling the function:

 #include #include using namespace std ; void laySoGiay ( unsigned long * par ); int main () { unsigned long sogiay ; laySoGiay ( & sogiay ); // in gia tri cout << "So giay la: " << sogiay << endl ; return 0 ; } void laySoGiay ( unsigned long * par ) { // Lay so giay hien tai * par = time ( NULL ); return ; } 

Running the above C ++ program will produce the following results:

Pass cursor to function in C ++ Picture 1

The function, which can accept a pointer, can accept an array as follows:

 #include using namespace std ; // khai bao ham: double giaTriTB ( int * arr , int size ); int main () { // mot mang so nguyen co 5 phan tu. int doanhSoBH [ 5 ] = { 122 , 35 , 27 , 235 , 60 }; double trungbinh ; // truyen con tro toi mang duoi dang mot tham so. trungbinh = giaTriTB ( doanhSoBH , 5 ) ; // hien thi ket qua cout << "Gia tri trung binh la: " << trungbinh << endl ; return 0 ; } double giaTriTB ( int * arr , int size ) { int i , sum = 0 ; double trungbinh ; for ( i = 0 ; i < size ; ++ i ) { sum += arr [ i ]; } trungbinh = double ( sum ) / size ; return trungbinh ; } 

When the above C ++ program is compiled and executed, it gives the following result:

 Gia tri trung binh la : 95.8 

According to Tutorialspoint

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