C++の練習を兼ねて, AtCoder Beginner Contest 303 の 問題C (Dash) ~ 問題D (Shift vs. CapsLock) を解いてみた.
■感想.
1. 問題C, Dは, 方針を絞り込めたので, AC版に到達できたと思う.
2. 個人的には, 苦手な動的計画法の訓練を積めたので, 非常に良かったと思う.
3. 引き続き, 時間を見つけて, 過去問の学習を進めていきたいと思う.
本家のサイト AtCoder Beginner Contest 303 解説 の 各リンク を ご覧下さい.
■C++版プログラム(問題C/AC版).
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 |
// C++(GCC 9.2.1) #include <bits/stdc++.h> using namespace std; using P = pair<int, int>; #define repex(i, a, b, c) for(int i = a; i < b; i += c) #define repx(i, a, b) repex(i, a, b, 1) #define rep(i, n) repx(i, 0, n) #define repr(i, a, b) for(int i = a; i >= b; i--) #define a first #define b second int main(){ // 1. 入力情報. int N, M, H, K; char c[202020]; scanf("%d %d %d %d %s", &N, &M, &H, &K, c); string S(c); set<P> st; rep(i, M){ int x, y; scanf("%d %d", &x, &y); st.insert({x, y}); } // 2. 移動. P cur = {0, 0}; bool ok = true; rep(i, N){ // 2-1. 体力消費. --H; // 2-2. 判定. if(H < 0){ ok = false; break; } // 2-3. 移動. if(S[i] == 'R') ++cur.a; if(S[i] == 'L') --cur.a; if(S[i] == 'U') ++cur.b; if(S[i] == 'D') --cur.b; // 2-4. 体力回復. if(H < K && st.count(cur)){ st.erase(cur); H = K; } } // 3. 出力. printf("%s\n", ok ? "Yes" : "No"); return 0; } |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 |
[入力例] 4 2 3 1 RUDL -1 -1 1 0 [出力例] Yes ※AtCoderテストケースより [入力例] 5 2 1 5 LDRLD 0 0 -1 -1 [出力例] No ※AtCoderテストケースより [入力例] 10 7 10 3 RULUDRDLDL -2 1 1 3 -7 1 -2 -1 -6 1 -3 2 -3 1 [出力例] Yes [入力例] 100 15 20 5 RUDDRLULURLDULUDURRDRDRLRLURDDULRDRULULDRURUDULRURDRLUURRRLLRDDDUURRLLUDUDLUURDUUURLULDULLUDLRULUUUU 7 -7 -4 3 5 -9 -2 -3 6 -3 1 -8 4 -4 -5 -10 6 7 10 -7 6 2 -7 -1 -10 -7 5 -10 -4 -2 [出力例] No [入力例] 250 25 30 32 DRRUDRULRULRUDLDLDLLUDUURULUULDLUDRUURRURDRLURLLRRRLUDLLLRLRDDUDRUUDRRUDLRUDLDUULRUULLRUUUDDLULDURRLRRDURRULLRDRLRDRUULLDLDRLDLDLULDUUURLUURRRLURULDLURDLRLLURDRURRURRLUULLUDLULURUURRDRRDDRRLRLULURDULULRUDLUDLUDLURDLRULDRULRDLULDULDRUUDDUUDDUDLDLDURUR 7 8 6 7 -9 2 6 4 5 6 -2 -5 -1 2 1 3 -4 4 -1 -2 3 -3 -2 5 2 -8 3 1 3 -5 3 21 -1 3 0 20 1 4 2 22 1 21 0 13 1 7 -2 3 -1 9 [出力例] Yes |
■C++版プログラム(問題D/AC版).
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 |
// C++(GCC 9.2.1) #include <bits/stdc++.h> using namespace std; using LL = long long; #define repex(i, a, b, c) for(int i = a; i < b; i += c) #define repx(i, a, b) repex(i, a, b, 1) #define rep(i, n) repx(i, 0, n) #define repr(i, a, b) for(int i = a; i >= b; i--) LL dp[303030][2]; int main(){ // 1. 入力情報. LL X, Y, Z; scanf("%lld %lld %lld", &X, &Y, &Z); char c[303030]; scanf("%s", c); string S(c); int N = S.size(); // 2. dp更新. dp[0][1] = Z; rep(i, N){ if(S[i] == 'a'){ dp[i + 1][0] = X + min(dp[i][0], dp[i][1] + Z); dp[i + 1][1] = Y + min(dp[i][0] + Z, dp[i][1]); } if(S[i] == 'A'){ dp[i + 1][0] = Y + min(dp[i][0], dp[i][1] + Z); dp[i + 1][1] = X + min(dp[i][0] + Z, dp[i][1]); } } // 3. 出力. printf("%lld\n", min(dp[N][0], dp[N][1])); return 0; } |
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 |
[入力例] 1 3 3 AAaA [出力例] 9 ※AtCoderテストケースより [入力例] 1 1 100 aAaAaA [出力例] 6 ※AtCoderテストケースより [入力例] 1 2 4 aaAaAaaAAAAaAaaAaAAaaaAAAAA [出力例] 40 ※AtCoderテストケースより [入力例] 7 5 3 aAAAAAaAaAAaaaAaaaAaAAAAAAaaaAAaAaaAAAAaaaaaAaaAAAaaAAaaaAAAAaaAAaaaaaaAAaaAAaAaAaaaaaAaAaAaaaAAaAaA [出力例] 578 [入力例] 2022 2023 2024 aAAAAaAaaaaaAAaaaaAAaaaaAaAAAaAAAAaaAaaaAaAaAAAAAAAaAAAAAaAaAAaaAaAAAAaAAAAAaaAAAAaAAaAAAaaaAaAAaaaaAaAAAAAAaaAAaAAaAAaaaaaaaaaAaaAaAAaAAAAAAaaaaaAaAAAaAaaAaAaaAaaAaaaaAAaaaAAaaaaAAaaAaaAaAaAAAaAaaAaaAAAaaaaaaaAAaaAAaaaAAAaaAAAaaaAaAAaAAaaAaaAAAaAAaAAAAaaAAaaAaaaAaAaAaaAaAAaAaAaAAAAaaAaAaAAaAAAaAAAaaaaAAaAAAaaaAAAaaAaaaaAAaAaAaAaAaAAaaAAaAAaAAAaaaAAAAaAaAaAaAAAaaAAAAAAAAaAAaaaaaAaaAaaAaaaAAAAaaaaAaaaAAAaaAAAAAAaaAAAaAaAaAAAaaAaAAAAaaAAaAaaaAaaAaaAAAaaAAAaaaaaaaaAAaaAaAaaAAaAaaAaAAaAAAAAAaAaaAAaA [出力例] 1011261 |
■参照サイト
日鉄ソリューションズプログラミングコンテスト2023(AtCoder Beginner Contest 303)