#include <stdio.h>
#define FILL 'X'
int main()
{
int i, r = 0;
char s[39 + 1];
s[r++] = FILL; s[r] = '\0';
for(i = 1; i <= 20; i++)
{
if(r > 40) // КОСТЫЛЬ
s[r++] = FILL; s[r++] = FILL; s[r] = '\0';
}
}
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