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c_cpp
a year ago
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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();
}
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