#include <stdio.h>
int main() {
int yu;
int count = 0;
for (int n = 1; n < 2020; n++) {
int temp = n;
while (temp > 0) {
if (temp % 10 == 9) {
count++;
break;
}
temp /= 10;
}
}
printf("%d", count);
return 0;
}
/* while(2019)
{
yu =n % 10;
if(yu==9) count++;
n/=10;
}*/

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