3、 Are formal and actual parameters in a programming language variables?

problem 1： What are formal and actual parameters ？

               Formal parameters are when we define functions , Parameters written in parentheses

              The argument is when we call the function , Incoming parameter

              The number of formal and actual parameters must be the same , The positions should correspond one by one , Data types should be compatible

problem 2： Are formal parameters and arguments a variable ？

              No , Formal and actual parameters are never a variable

Let's verify whether the arguments and formal parameters are variables  

#include <iostream>
#include <stdio.h>
using namespace std;
void test(int i)
{
    i = 99;
    printf(" Shape parameter i The address for :%#X\n", &i);
}
int main(int argc, char const *argv[])
{
    int i = 6;
    printf(" Actual parameters i The address for %#X\n", &i);
    test(i);
    printf(" after test Function to get i  by  %d\n", i);
    return 0;
}

i By function test after ,i The value of has not changed , And the shape parameter i And real parameters i The address of is different , This further illustrates that arguments and formal parameters are not variables .