Codeforces Round #276 (Div. 2) C. Bits (constructor)

You can directly construct the answer to this question.

For the binary representation of l, change it from right to left to 1. If it cannot be changed again (then l is greater than r), the answer is l.

This method ensures that the answer is greater than or equal to l and less than or equal to r, and that the value of 1 in binary representation is the most.

# Include <iostream> # include <cstdio> # include <cstdlib> # include <cstring> # include <string> # include <cmath> # include <map> # include <set> # include <vector> # include <algorithm> # include <stack> # include <queue> # include <cctype> # include <sstream> using namespace std; # define pii pair <int, int> # define LL long intconst int eps = 1e-8; const int INF = 1000000000; const int maxn = 10000 + 5; int n; LL l, r, p; int main () {// freopen ("in9.txt", "r", stdin); // freopen ("out.txt", "w", stdout ); scanf ("% d", & n); while (n --) {scanf ("% I64d % I64d", & l, & r); p = 1; while (1) {if (l | p)> r) {printf ("% I64d \ n", l); break;} else {l | = p; p * = 2 ;}}// fclose (stdin); // fclose (stdout); return 0 ;}

 

Codeforces Round #276 (Div. 2) C. Bits (constructor)