Create Recurssion.cpp

maths/Recurssion.cpp

@@ -0,0 +1,42 @@
+#define MAX 50
+int dp[MAX][MAX][MAX][MAX][4];
+
+int permutationpos(int x,int y,int z,int w,int last)
+{
+    if(x<0||y<0||z<0||w<0)
+        return 0;
+
+    if(x==1 && y==0 && z==0 && w==0 && last==0)
+        return 1;
+    if(x==0&&y==1&&z==0&&w==0&&last==1)
+        return 1;
+    if(x==0&&y==0&&z==1&&w==0&&last==2)
+        return 1;
+    if(x==0&&y==0&&z==0&&w==1&&last==3)
+        return 1;
+    if(dp[x][y][z][w][last]!=-1)
+        return dp[x][y][z][w][last];
+    if(last==0)
+       dp[x][y][z][w][last]=permutationpos(x-1,y,z,w,1)+permutationpos(x-1,y,z,w,2)+permutationpos(x-1,y,z,w,3);
+    else if(last==1)
+       dp[x][y][z][w][last]=permutationpos(x,y-1,z,w,0)+permutationpos(x,y-1,z,w,2)+permutationpos(x,y-1,z,w,3);
+    else if(last==2)
+       dp[x][y][z][w][last]=permutationpos(x,y,z-1,w,1)+permutationpos(x,y,z-1,w,0)+permutationpos(x,y,z-1,w,3);
+    else
+       dp[x][y][z][w][last]=permutationpos(x,y,z,w-1,1)+permutationpos(x,y,z,w-1,2)+permutationpos(x,y,z,w-1,0);
+
+    return dp[x][y][z][w][last];
+}
+
+void solve()
+{
+	int x,y,z,w;
+	cin>>x>>y>>w>>z;
+	int rearrange;
+	mem1(dp);
+	rearrange = permutationpos(x,y,z,w,0)+
+                permutationpos(x,y,z,w,1)+
+                permutationpos(x,y,z,w,2)+
+                permutationpos(x,y,z,w,3);
+	cout<<rearrange<<"\n";
+}