diff --git a/hdu/6889.cpp b/hdu/6889.cpp
new file mode 100644
index 0000000..b62be2e
--- /dev/null
+++ b/hdu/6889.cpp
@@ -0,0 +1,118 @@
+#define _CRT_SECURE_NO_WARNINGS
+#define _SILENCE_CXX17_C_HEADER_DEPRECATION_WARNING
+#include <bits/stdc++.h>
+using namespace std;
+#define CRP(t, x) const t &x
+#define OPX(op, t, x) operator op(CRP(t, x))
+#define OPL(t, x) bool OPX(<, t, x) const
+#define FIL(x, v) memset(x, v, sizeof(x))
+#define CLR(x) FIL(x, 0)
+#define NE1(x) FIL(x, -1)
+#define INF(x) FIL(x, 0x3f)
+#ifndef _DEBUG
+#define _DEBUG 0
+#endif // !_DEBUG
+#define IFD if (_DEBUG)
+typedef int64_t ll, i64;
+typedef uint64_t ull, u64;
+template <typename... Types>
+using comtype = typename common_type<Types...>::type;
+template <typename T>
+using enable_if_arithmetic = typename enable_if<is_arithmetic<T>::value>::type;
+template <typename T>
+using enable_if_integral = typename enable_if<is_integral<T>::value>::type;
+inline char getchar(int)
+{
+    static char buf[64 << 20], *S = buf, *T = buf;
+    if (S == T) T = fread(S = buf, 1, 64 << 20, stdin) + buf;
+    return S == T ? EOF : *S++;
+}
+template <typename T, typename = enable_if_integral<T>>
+inline bool read(T &x)
+{
+    int ch = x = 0, f = 1;
+    while (!isdigit(ch = getchar()))
+        if (ch == EOF)
+            return false;
+        else if (ch == '-')
+            f = 0;
+    for (; isdigit(ch); ch = getchar()) x = x * 10 + ch - '0';
+    return x = f ? x : -x, true;
+}
+template <typename T, typename... Args, typename = enable_if_integral<T>>
+inline bool read(T &x, Args &... args) { return read(x) && read(args...); }
+template <typename T1, typename T2, typename TResult = comtype<T1, T2>>
+inline TResult mmin(CRP(T1, v1), CRP(T2, v2)) { return min<TResult>(v1, v2); }
+template <typename T, typename... Args, typename TResult = comtype<T, Args...>>
+inline TResult mmin(CRP(T, v), const Args &... args) { return min<TResult>(v, mmin(args...)); }
+template <typename T1, typename T2, typename TResult = comtype<T1, T2>>
+inline TResult mmax(CRP(T1, v1), CRP(T2, v2)) { return max<TResult>(v1, v2); }
+template <typename T, typename... Args, typename TResult = comtype<T, Args...>>
+inline TResult mmax(CRP(T, v), const Args &... args) { return max<TResult>(v, mmax(args...)); }
+inline ll gcd(ll a, ll b)
+{
+    for (; b; swap(a, b)) a %= b;
+    return a;
+}
+inline ll fpow(ll a, ll b, ll m)
+{
+    ll r = 1;
+    for (; b; b >>= 1, a = a * a % m)
+        if (b & 1) r = r * a % m;
+    return r;
+}
+constexpr double eps = 1e-8;
+inline int sgn(double x) { return x > eps ? 1 : x < -eps ? -1 : 0; }
+const int N = 1000010;
+int prime[N], id1[N], id2[N], flag[N], ncnt, m;
+ll g[N], sum[N], a[N], T, n;
+inline int ID(ll x) { return x <= T ? id1[x] : id2[n / x]; }
+inline ll calc(ll x) { return x * (x + 1) / 2 - 1; }
+inline ll f(ll x) { return x; }
+void init()
+{
+    T = sqrt(n + 0.5);
+    for (int i = 2; i <= T; i++)
+    {
+        if (!flag[i]) prime[++ncnt] = i, sum[ncnt] = sum[ncnt - 1] + i;
+        for (int j = 1; j <= ncnt && i * prime[j] <= T; j++)
+        {
+            flag[i * prime[j]] = 1;
+            if (i % prime[j] == 0) break;
+        }
+    }
+    for (ll l = 1; l <= n; l = n / (n / l) + 1)
+    {
+        a[++m] = n / l;
+        if (a[m] <= T)
+            id1[a[m]] = m;
+        else
+            id2[n / a[m]] = m;
+        g[m] = calc(a[m]);
+    }
+    for (int i = 1; i <= ncnt; i++)
+        for (int j = 1; j <= m && (ll)prime[i] * prime[i] <= a[j]; j++)
+            g[j] = g[j] - (ll)prime[i] * (g[ID(a[j] / prime[i])] - sum[i - 1]);
+}
+
+ll calc1(ll _n, ll mod)
+{
+    __int128 x = _n;
+    return ((2 + x + 1) * x / 2 - 4) % mod;
+}
+int main()
+{
+    n = 1e10 + 10;
+    init();
+    int T;
+    ll __N, mod;
+    read(T);
+    while (T--)
+    {
+        read(__N, mod);
+        ll ans = calc1(__N, mod);
+        ans = ans + g[ID(__N + 1)];
+        printf("%lld\n", ans % mod);
+    }
+    return 0;
+}
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