How to find the capacity of Channel, Pointer and Slice in Golang?

// Go program to illustrate how to find the 
// capacity of the pointer 
package main 
  
import ( 
    "fmt"
) 
  
// Main function 
func main() { 
  
    // Creating and initializing 
    // pointer
    // Using var keyword 
    var ptr1 [7]*int
    var ptr2 [5]*string 
    var ptr3 [8]*float64 
  
    // Finding the capacity of 
    // the pointer
    // Using cap function 
    fmt.Println("Capacity of ptr1: ", cap(ptr1)) 
    fmt.Println("Capacity of ptr2: ", cap(ptr2)) 
    fmt.Println("Capacity of ptr3: ", cap(ptr3)) 
  
} 

// Go program to illustrate how to find the 
// capacity of the Channel
package main 
  
import ( 
    "fmt"
) 
  
// Main function 
func main() { 
  
    // Creating and initializing 
    // Channel
    // Using var keyword 
    ch1 := make(chan int, 7) 
    ch2 := make(chan string, 5)
    ch3 := make(chan float64, 8)
  
    // Finding the capacity of 
    // the Channel
    // Using cap function 
    fmt.Println("Capacity of Channel1: ", cap(ch1)) 
    fmt.Println("Capacity of Channel2: ", cap(ch2)) 
    fmt.Println("Capacity of Channel3: ", cap(ch3)) 
  
} 

// Go program to illustrate how to find the 
// capacity of the Slice 
package main 
  
import ( 
    "fmt"
) 
  
// Main function 
func main() { 
  
    // Creating and initializing 
    // Slice 
    // Using var keyword 
    sl1 := make([]int, 0, 7) 
    sl2 := make([]string, 0, 5)
    sl3 := make([]float64, 0, 8)
  
    // Finding the capacity of 
    // the Slice 
    // Using cap function 
    fmt.Println("Capacity of Slice1: ", cap(sl1)) 
    fmt.Println("Capacity of Slice2: ", cap(sl2)) 
    fmt.Println("Capacity of Slice3: ", cap(sl3)) 
  
}