2022-03-29 topcoder srm826 practice. Solved A. This website is bad enough to make me maybe not wanna solve more unless I find better tools.

Author: dcclyde

topcoder/2022-03-29_srm826/A.cpp

@@ -0,0 +1,56 @@
+
+// ! ---------------------------------------------------------------------------
+
+#include <bits/stdc++.h>
+using ll = long long;
+using namespace std;
+template<class T> using V = vector<T>;
+
+
+
+struct TwoFairDice {
+
+    ll finish(vector<int>& A, vector<int>& B) {
+        vector<ll> helper(13);  // h[k] = num ways to have 2*W + Draws add up to k.
+
+        auto get_score = [&](int k) {
+            int score = 0;
+            for ( int idx = 0 ; idx < 6 ; ++idx ) {
+                if ( k > A[idx] ) {
+                    score += 2;
+                } else if ( k == A[idx] ) {
+                    score += 1;
+                }
+            }
+            return score;
+        };
+
+        for ( int k = 0 ; k <= 1000 ; ++k ) {
+            int score = get_score(k);
+            ++helper[score];
+        }
+
+        V<V<ll>> dp(7, V<ll>(73));
+        // insert the faces we're already given.
+        int score_already = 0;
+        int faces_already = 0;
+        for ( auto& x : B ) {
+            int score = get_score(x);
+            score_already += score;
+            ++faces_already;
+        }
+        dp[faces_already][score_already] = 1;
+
+        for ( int face = faces_already ; face < 6 ; ++face ) {
+            for ( int score = 0 ; score <= 12 ; ++score ) {
+                ll ways = helper[score];
+                for ( int prev_score = 0 ; prev_score <= 36 ; ++prev_score ) {
+                    dp[face + 1][prev_score + score] += dp[face][prev_score] * ways;
+                }
+            }
+        }
+
+        return dp[6][36];
+    }
+};
+