update

src/P2822/P2822.cpp

@@ -1,6 +1,37 @@
 #include <iostream>
+#include <algorithm>
 
+using ull = unsigned long long;
+
+static ull t, k, n, m, ans;
+
+static constexpr ull fact(const ull n)noexcept{
+    if(n==0)return 1;
+    ull ret {1};
+    for(ull i{2};i<=n;i++){
+        ret*=i;
+    }
+    return ret;
+}
+
+static constexpr ull C(const ull n, const ull m)noexcept{
+    return fact(n)/(fact(m)*fact(n-m));
+}
+
+#define NV(v)#v<<" : "<<(v)
 
 int main(){
+    // std::cout<<NV(fact(0))<<'\n'<<NV(fact(3))<<'\n';
+    std::iostream::sync_with_stdio(false), std::cin.tie(nullptr), std::cout.tie(nullptr);
+    std::cin>>t>>k;
 
+    for(ull i {0};i<t;i++){
+        std::cin>>n>>m;
+        for(ull i {0};i<=n;i++){
+            for(ull j{0};j<=std::min(i,m);j++){
+                if(C(i,j)%k==0)ans++;
+            }
+        }
+        std::cout<<ans<<'\n';
+    }
 }