又是为自己的无知流泪的一年
一. 网易雷火笔试 300’ 第一题26个字母分别算个斐波那契就行第二题是个小贪心，按价值从大到小排个序，从最大的开始杀，杀这个数最好的时间就是他消失之前的那个时间点。第三题一个模拟，按题目要求模拟就行第四题四元数坑了我，最后20分钟调出了样例交上去还是0分，这题我实在没法手出样例算了，有时间好好再学学四元数，再调吧，放一个没A的代码省的删了。
// Didn't AC #define _CRT_SECURE_NO_WARNINGS#include <iostream>#include <cstdio>#include <algorithm>#include <cstring>#include <cmath>#include <vector>#include <list>#include <set>#include <map>#include <unordered_map>using namespace std;struct quaternion{double t;double x; double y; double z;};quaternion mul(quaternion left, quaternion right){quaternion ans;double d1, d2, d3, d4;d1 = left.t * right.t;d2 = -left.x * right.x;d3 = -left.y * right.y;d4 = -left.z * right.z;ans.t = d1 + d2 + d3 + d4;d1 = left.t * right.x;d2 = right.t * left.x;d3 = left.y * right.z;d4 = -left.z * right.y;ans.x = d1 + d2 + d3 + d4;d1 = left.t * right.y;d2 = right.t * left.y;d3 = left.z * right.x;d4 = -left.x * right.z;ans.y = d1 + d2 + d3 + d4;d1 = left.t * right.z;d2 = right.t * left.z;d3 = left.x * right.y;d4 = -left.y * right.x;ans.z = d1 + d2 + d3 + d4;return ans;}quaternion VtoQ(double PosX, double PosY, double PosZ){quaternion ans;ans.t = 0.0;ans.x = PosX;ans.y = PosY;ans.z = PosZ;return ans;}int n;vector<int> ch[2001];quaternion node[2001];quaternion coor[2001];int fa[2001],root;double Tdata[2001][20][10];int m[2001];void rotate(int p, quaternion q) {quaternion qq;qq.x = -q.x;qq.y = -q.y;qq.z = -q.z;qq.t = q.t;for (auto it : ch[p]) {node[it] = mul(qq, node[it]);node[it] = mul(node[it],q);rotate(it, q);}return;}void getans(int p) {for (auto it : ch[p]) {coor[it].x = coor[p].x + node[it].x;coor[it].y = coor[p].y + node[it].y;coor[it].z = coor[p].z + node[it].z;coor[it].t = coor[p].t + node[it].t;getans(it);}}quaternion line(quaternion q0, quaternion q1,double s) {q0.t *= (1.0f-s);q0.x *= (1.0f-s);q0.y *= (1.0f-s);q0.z *= (1.0f-s);q1.t *= s;q1.x *= s;q1.y *= s;q1.z *= s;quaternion ans;ans.x = q0.x + q1.x;ans.y = q0.y + q1.y;ans.z = q0.z + q1.z;ans.t = q0.t + q1.t;double xx = ans.x * ans.x;double yy = ans.y * ans.y;double zz = ans.z * ans.z;double tt = ans.t * ans.t;double ss = sqrt(xx + yy + zz + tt);ans.t /= ss;ans.x /= ss;ans.y /= ss;ans.z /= ss;return ans;}int main() {scanf("%d", &n);for (int i = 0; i < n; i++) {int a;double x, y, z;cin >> a >> x >> y >> z;if (a != -1) ch[a].push_back(i);else root = i;fa[i] = a;node[i] = VtoQ(x, y, z);}for (int i = 0; i < n; i++) {cin >> m[i];for (int j = 0; j < m[i]; j++) {for (int k = 0; k < 5; k++)cin >> Tdata[i][j][k];}}double T; cin >> T;for (int i = 0; i < n; i++) {double LastTime = 0;quaternion LastQ;for (int j = 0; j < m[i]; j++) {double time = Tdata[i][j][0];quaternion q = {Tdata[i][j][2], Tdata[i][j][3], Tdata[i][j][4], Tdata[i][j][1] };if (time <= T) {rotate(i, q);}else {quaternion temp = line(LastQ, q, (T - LastTime) / (time-LastTime));rotate(i, temp);break;}LastTime = time;LastQ = q;}}getans(root);for (int i = 0; i < n; i++) {printf("%.2lf %.2lf %.2lf\n", coor[i].x, coor[i].y, coor[i].z);}return 0;}
