اكواد c++ تخص المصفوفات two dimensional array

#include<iostream.h>
main()
{
const int n=3,m=3;
int a[n][m],i,j;
for(i=0;i<n;i++)
for(j=0;j<m;j++){
cout<<"a["<<i<<"]=";
cin>>a[i][j];}
for(i=0;i<n;i++)
for(j=0;j<m;j++){
if(a[i][j]>=0&&a[i][j]%2==0)
cout<<a[i][j]<<"\t";}
}

#include<iostream.h>
main()
{
const int n=3,m=3;
int a[n][m],i,j;
for(i=0;i<n;i++)
for(j=0;j<m;j++){
cout<<"a["<<i<<"]=";
cin>>a[i][j];}
for(i=0;i<n;i++)
for(j=0;j<m;j++){
if(a[i][j]<0&&a[i][j]%2!=0)
cout<<a[i][j]<<"\t";}
}

#include<iostream.h>
void main()
{
const int m=3,n=3;int count=0;
int x;
cout<<"enter x :";
cin>>x;
int s[n][m];
for(int i=0;i<n;i++)
for(int j=0;j<m;j++)
{cin>> s[i][j];

if(s[i][j]==x)
count ++;}
cout<<" x is repeated "<<count<<" often";
}

#include<iostream.h>
main()
{
const int n=3,m=4;
int i,j,sum;
sum=0;
int a[n][m];
for(i=0;i<n;i++)
for(j=0;j<m;j++)
cin>>a[i][j];
for(i=0;i<n;i++)
for(j=0;j<m;j++) {
if(a[i][j]%2==0)
sum+=a[i][j];
}
cout<<"\n sum = "<<sum; }