Why this C++ code is giving wrong output?

Question

I wrote a program which takes user input ten times and than outputs their average in C++. But my program is giving 0 as output. I can't figure out where is the problem. Please Help.

This is the code:

#include <iostream>
using namespace std;

void calc(int arg){
int i;
cin>>i;
arg += i;
}

int main(){
int sum = 0;
for(int i=1; i<=10;i++){
calc(sum);
}
int o = sum/10;
cout<<o;
return 0;
}

Answer 1

Change the signature for function calc to accept its argument by reference rather than by value.

void calc( int& arg )

Also it is recommended to use a floating point type for variable <o> because integer division ignores decimal points in the division result.

double o = (double)sum / 10;

Answer 2

Because u are calling calc by value not buy it's reference and you are storing result of a division into an int which is not good practice.

try this program here I am calling calc by its reference so changes in arg directly reflect to sum. and using flot o instead of int o

#include <iostream>
using namespace std;

void calc(int *arg){
int i;
cin>>i;
*arg += i;
}

int main(){
int sum = 0;
for(int i=1; i<=10;i++){
calc(&sum);
}
float o = sum/10;
cout<<o;
return 0;
}