题解 | #坐标移动#
坐标移动
https://www.nowcoder.com/practice/119bcca3befb405fbe58abe9c532eb29
画出dfa(确定性有限自动机)即可
// https://www.nowcoder.com/practice/119bcca3befb405fbe58abe9c532eb29 #include <iostream> using namespace std; using ii = pair<int, int>; using handle = void (*)(int); const int maxn = 5 + 1e4; handle accept[maxn]; int trans[maxn][128], tsiz; // t[u][x] = v: u --x--> v ii dxs[128]; string s; // input ii ans; void accept5(int p) { // a1; ii dx = dxs[s[p - 2]]; int length = s[p - 1] - '0'; dx.first *= length, dx.second *= length; ans.first += dx.first, ans.second += dx.second; // cout << s.substr(p - 2, 2) << endl; // printf("%d,%d\n", ans.first, ans.second); } void accept6(int p) { // a11; ii dx = dxs[s[p - 3]]; int length = 10 * (s[p - 2] - '0') + s[p - 1] - '0'; dx.first *= length, dx.second *= length; ans.first += dx.first, ans.second += dx.second; // cout << s.substr(p - 3, 3) << endl; // printf("%d,%d\n", ans.first, ans.second); } void init() { dxs['W'] = {0, 1}; dxs['S'] = {0, -1}; dxs['A'] = {-1, 0}; dxs['D'] = {1, 0}; trans[0][';'] = 1; // 0 是非法状态,即如果没有转移,那么会转移到这个节点 trans[1]['W'] = 2, trans[1]['A'] = 2, trans[1]['S'] = 2, trans[1]['D'] = 2; trans[1][';'] = 1; for (int i = '0'; i <= '9'; ++i) trans[2][i] = 3; trans[2][';'] = 1; for (int i = '0'; i <= '9'; ++i) trans[3][i] = 4; trans[3][';'] = 5; // a1 trans[4][';'] = 6; // a11 trans[5]['W'] = 2, trans[5]['A'] = 2, trans[5]['S'] = 2, trans[5]['D'] = 2; accept[5] = accept5; // 5 是接受状态 trans[6]['W'] = 2, trans[6]['A'] = 2, trans[6]['S'] = 2, trans[6]['D'] = 2; accept[6] = accept6; // 6 是接受状态 } int main() { init(); cin >> s; int u = 1; for (int i = 0; i < s.size(); ++i) { u = trans[u][s[i]]; // cout << u << " "; if (accept[u] != nullptr) accept[u](i); } printf("%d,%d", ans.first, ans.second); }