오답

baekjoon/cpp/c++/5546.cpp

@@ -0,0 +1,77 @@
+#include <bits/stdc++.h>
+
+const int MOD = 10000;
+int n, k;
+
+int dp[101][4][3];
+int selected[101];
+
+void getinput()
+{
+ std::cin >> n >> k;
+ for (int i = 0; i < k; i++)
+ {
+ int a, b;
+ std::cin >> a >> b;
+ selected[a] = b;
+ }
+}
+
+// 오늘은 day이고, 어제 prev를 먹었다. 연속해서 먹은 횟수는 streak.
+int solve(int day, int prev, int streak)
+{
+ if (streak == 3)
+ return 0;
+ auto &ret = dp[day][prev][streak];
+ if (ret != -1)
+ return ret;
+ if (day == n)
+ return ret = (streak < 3);
+
+ ret = 0;
+ if (selected[day])
+ {
+ if (prev == selected[day] && streak == 2)
+ return ret = 0;
+ auto next_streak = (prev == selected[day] ? streak + 1 : 1);
+ return ret = solve(day + 1, selected[day], next_streak);
+ }
+ else
+ {
+ for (int i = 1; i <= 3; i++)
+ {
+ // day에 i번 파스타를 먹음
+ auto next_streak = (prev == i ? streak + 1 : 1);
+ ret = (ret + solve(day + 1, i, next_streak)) % MOD;
+ }
+ return ret;
+ }
+}
+
+int solve()
+{
+ std::memset(dp, -1, sizeof(dp));
+ if (selected[1])
+ {
+ int ans = solve(2, selected[1], 1);
+ return ans;
+ }
+ else
+ {
+ int ans = 0;
+ for (int i = 1; i <= 3; i++)
+ {
+ ans = (ans + solve(2, i, 1)) % MOD;
+ }
+ return ans;
+ }
+}
+
+int main()
+{
+ std::ios::sync_with_stdio(false);
+ std::cin.tie(0);
+
+ getinput();
+ std::cout << solve() << '\n';
+}