#include <iostream>
using namespace std;
bool Check(int num){
return (num >= 7777) ? true : false;
}
int main(){
// 探索範囲は[lo, hi]
int lo = 1;
int hi = 100000;
while(lo < hi) {
// printf("lo, hi = %d, %d\n", lo, hi);
int k = (lo + hi) / 2;
if (Check(k))
hi = k;
else
lo = k + 1;
}
cout << lo << endl;
return 0;
}
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