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Dropping the lowest number in an array

and kand 97 (30)
I have a homework assignment that asks me to enter 10 grades into an array then find the average after dropping the lowest grade. I got the average part down easy but I can't figure out how to drop the lowest grade. I tried this but got an average of zero which isn't right. Help...?

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  #include<iostream>

using namespace std;

int main(){

    int total = 0;
    const int size = 10;
    double avg;

    int grades[size] = {76,87,99,54,78,98,65,86,84,100};

    for(int i = 0; i<size; i++){
          if(grades[size]<grades[i-1]){
      total+=grades[i];
    }

    }

    avg= total/size;
        cout<< "The average is : "<< avg <<endl;
    return 0;

}
JLBorges (13770)
What are you tring to do here? if(grades[size]<grades[i-1])

grades[size]: out of range access, the last grade is at grades[size-1]

grades[i-1]: out of range access, when i == 0

This is integer division: avg = total/size;


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int main(){

    const int size = 10;

    int grades[size] = {76,87,99,54,78,98,65,86,84,100};
    int total = 0;
    int lowest = grades[0] ;

    for( int i = 0; i<size; ++i ) {

      total += grades[i];
      if( lowest > grades[i] ) lowest = grades[i] ;
    }


    const double avg = double(total) / size; 

    const int total_excluding_lowest = total - lowest ;
    const double avg_excluding_lowest = double(total_excluding_lowest) / (size-1); // size > 1

    // ...
}
Last edited on
and kand 97 (30)
...I had the average part without dropping the lowest... What I posted is my attempt at dropping the lowest. Sorry I wasn't clear enough. Thanks for the help anyway.
JLBorges (13770)
> I had the average part without dropping the lowest... What I posted is my attempt at dropping the lowest.

Ok. I'm sorry that my post didn't take that possibility into account. (Edited now).
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