Confusion about passing arrays [closed] - c++

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Can someone help me with my program? I need to pass the three arrays into the function called calc_volts and then calculated the volts and then display the values. I keep getting errors that say "unreferenced local variable" or "undeclared idebtufier" for the variables; i, j, k, and volts.
#include <iomanip>
#include <iostream>
#include <cmath>
using namespace std;
double calc_volts(double, double, double, int);
int main()
{
const int max = 10;
int i; double current[max] = {10.62,14.89,13.21,16.55,19.62,9.47,6.58,18.32,12.15,3.98};
int j; double volts[max];
int k; double resistance[max] = {4,8.5,6,7.35,9,15.3,3,5.4,2.9,4.8};
}
double calc_volts(double current[],double volts[], double resistance[], int max)
{
for (j = 0, j<max, j++)
volts[j] = current[i]*resistance[k];
return volts[j];
}

Answer 1

You have many problems:
Your function declaration is wrong:
double calc_volts(double, double, double, int);
It should be:
double calc_volts(double[], double[], double[], int);
You must invoke the function in order to use it:
int main()
{
const int max = 10;
double current[max] = {10.62,14.89,13.21,16.55,19.62,9.47,6.58,18.32,12.15,3.98};
double volts[max];
double resistance[max] = {4,8.5,6,7.35,9,15.3,3,5.4,2.9,4.8};
calc_volts(current, volts, resistance, max); // call the function to execute it
}
The variables i, j and k do not exist inside calc_volts because they were declared inside main. Variables declared inside a function can only be used inside that function.
To fix the problem just put the declarations inside calc_volts.