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#include <iostream>
#include <cstdio>
#include <cmath>

using namespace std;
int main() {
// a) 1 QUESTION
int n;
double A[11][11] = { 0.0 }; // why do we have to initialize A to 0;
cout << "input n =";
cin >> n;


//b) UNDERSTOOD
if(n<1) n=1;
if(n>10) n=10;


//c) UNDERSTOOD
for(i=0;i<=n;i++){
    for(j=0;j<=n;j++){
        A[i][j] = -2.0*i + j*j;
    }
}


//d) 3 QUESTIONS
double min_A, max_A, count_zero;
int count;
min_A = max_A = A[1][1]; // how come the max and min are equal to the same element
count = 0;
 for(i=1;i<=n;i++) {
     for(j=1;j<=n;j++) {
         if(A[i][j] > max_A) max_A = A[i][j]; //can you explain the logic 
         if(A[i][j] < min_A) min_A = A[i][j]; //can you explain the logic 
         if ( abs(A[i][j]) < 1.0e-10 ) count++;
         // note you should not normally use == with doubles due to round
         // off error
     }
 }


//e) UNDERSTOOD
 for(j=1;j<=n;j++)
 {
     A[1][j] = 2*A[1][j]-A[2][j];
}


getchar(); 	
return 0;
}