double d=10; double darr[]={3.0,0.5,2.0,1.5}; for(int i=0;i<4;i++){d*=darr[I];} cout<<d;

Question

Why is output 4.5 ???

Answer 1

The output is 45 because you can see in the for loop it use the assignment operator which is Multiplication (*=)

Then the assignment statement is d*=darr[i]

Its look like these when the loop iterate

10 *=3.0
=30
10 *=0.5
=15
10 *=2.0
=30
10 *=1.5
=45

Answer 2

#include <iostream>
using namespace std;

int main() {
double d=10;
double darr[]={3.0,0.5,2.0,1.5};
for(int i=0;i<4;i++){
d*=darr[i];
}
cout<<d;

}

10 * 3.0 * 0.5 * 2.0 * 1.5 = 45.0