How to count negatives? [closed] - c++

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I wrote this code and the output is not coming as expected. The function returns the negatives recursively. But it is not doing returning what it should be.
size_t recursive_x(stack<int> mystack){
int count=0;
if(!mystack.empty()){
if(mystack.top()<0){
count+=1;
}
mystack.pop();
count+=recursive_x(mystack);
}cout<<count<<endl;
return count;
}
int main(){
stack<int> mystack;
mystack.push(9);
mystack.push(-2);
mystack.push(-2);
mystack.push(1);
mystack.push(-3);
mystack.push(-1);
mystack.push(99);
mystack.push(-1);
mystack.push(1);
mystack.push(1);
recursive_x(mystack);
}
The output should be 5 but it is coming like this:
Output:
0
0
1
2
2
3
4
4
5
5
5

Answer 1

Assuming you do call the function, the output is exactly what I would expect.
The display shows the number of negative numbers on the stack at the point where
cout<<count<<endl;
is invoked.
It is invoked first for the innermost recursion, because you make your recursive call before doing any output for the current recursion.
count+=recursive_x(mystack);
}cout<<count<<endl;
If you just want the output 5, you could print the result returned from your initial call
int finalCount = recursive_x(mystack);
cout<<finalCount<<endl;
and remove the output in recursive_x().

Answer 2

Each recursive call will print the result.
You just need to move the print command to the main:
size_t recursive_x(stack<int> mystack){
int count=0;
if(!mystack.empty()){
if(mystack.top()<0){
count+=1;
}
mystack.pop();
count+=recursive_x(mystack);
}
return count;
}
int main(){
stack<int> mystack;
mystack.push(9);
mystack.push(-2);
mystack.push(-2);
mystack.push(1);
mystack.push(-3);
mystack.push(-1);
mystack.push(99);
mystack.push(-1);
mystack.push(1);
mystack.push(1);
cout<<recursive_x(mystack)<<endl;
}
Output:
5