#include <iostream>
#define MAX 1500
using namespace std;
int main()
{
int i, j, plano[MAX][MAX]={}, area=0;
for(i=0; i<MAX; i++){
for(j=0; j<MAX; j++){
if(plano[i][j]==1) area+=1;
}
}
cout<<area;
return 0;
}
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