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c_cpp
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#include <bits/stdc++.h>
using namespace std;
#define int int64_t
const int MOD = 1e9 + 7;
int mpow(int x, int y)
{
int res = 1;
if (x == 0)return 0;
while (y > 0)
{
if (y % 2) res = (res * x);
y /= 2;
x = (x * x);
}
return res;
}
void solve() {
int n, k;
cin >> n >> k;
int curr = 0, prev = 0;
bool flag = 1;
int ans = 0;
while(prev < n) {
if(flag) {
for(int i = 0; i < 62 && __builtin_popcountll(curr) <= k; i++) {
if(!(mpow(2, i) & curr)) {
curr += mpow(2, i);
}
}
curr = min(curr, n);
int x = (curr - prev) % MOD;
x *= (x + 1);
if(x % 2) x += MOD;
x /= 2;
ans += x;
ans %= MOD;
} else {
int start = __lg(curr) + 1;
int store = __builtin_ctzll(curr);
curr -= mpow(2, store);
if(__builtin_popcountll(curr) + __builtin_ctzll(curr) == start) {
curr = mpow(2, start);
} else {
int pos = __builtin_ctzll(curr);
while(curr & mpow(2, pos)) {
curr -= mpow(2, pos);
pos++;
}
curr += mpow(2, pos);
}
curr = min(curr, n);
}
flag ^= 1;
prev = curr;
} cout << ans << '\n';
}
int32_t main() {
ios_base::sync_with_stdio(false);
cin.tie(nullptr);
int _aditya_b = 1;
cin >> _aditya_b;
while (_aditya_b--) solve();
}Editor is loading...
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