#include <iostream>
using namespace std;
int main() {
int n;
cin >> n;
if( ( 0 <= n ) and ( n <= 9 ) ) cout << 1;
else if( ( 10 <= n ) and ( n <= 99 ) ) cout << 2;
else if( ( 100 <= n ) and ( n <= 999 ) ) cout << 3;
else if( ( 1000 <= n ) and ( n <= 9999 ) ) cout << 4;
else if( ( 10000 <= n ) and ( n <= 99999 ) ) cout << 5;
else if( ( 100000 <= n ) and ( n <= 999999 ) ) cout << 6;
else if( ( 1000000 <= n ) and ( n <= 9999999 ) ) cout << 7;
else if( ( 10000000 <= n ) and ( n <= 99999999 ) ) cout << 8;
else if( ( 100000000 <= n ) and ( n <= 999999999 ) ) cout << 9;
else if( ( 1000000000 <= n ) and ( n <= 2000000000 ) ) cout << 10;
return 0;
}
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