Create 431C.cpp

431C.cpp

@@ -0,0 +1,42 @@
+#include <bits/stdc++.h>
+#define ll long long int
+#define MOD 1000000007
+using namespace std;
+
+ll dp[100][2];
+
+int min(int a, int b){
+	if(a<b) return a;
+	else return b;
+}
+
+ll solve(ll n, ll k, ll d){
+	for(int i=1;i<=n;i++){
+		for(int j=1;j<=min(i,k);j++){
+			if(j<d){
+				dp[i][0] += dp[i-j][0];
+				dp[i][0]%=MOD;
+
+				dp[i][1] += dp[i-j][1];
+				dp[i][1]%=MOD;
+			}
+			else{
+				dp[i][1] += dp[i-j][0];
+				dp[i][1]%=MOD;
+				dp[i][1] += dp[i-j][1];
+				dp[i][1]%=MOD;
+			}
+		}
+	}
+	return dp[n][1];
+}
+
+int main(){
+	// Initialise values
+	dp[0][0] = 1; //No restrictions
+	dp[0][1] = 0; //Initially impossible
+
+	ll n,k,d;
+	cin>>n>>k>>d;
+	cout<<solve(n,k,d)<<"\n";
+}