#include <stdio.h>
int main(void) {
int N;
int i;
int c=1;
int r=0;
int p=0;
for(i=1; i<=N; i++){
if(i%2!=0){
c=c+1;
//printf("%d\n", c);
r=(c-1);
//printf("%d\n", r);
p=c*r;
//printf("%d\n", p);
}
else{
c=(i/2)+1;
//printf("%d\n", c);
r=(i/2)+1;
//printf("%d\n", r);
p=c*r;
//printf("%d", p);
}
}
return 0;
}
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