zoj 2771 Get Out of the Glass

zoj 2771 Get Out of the Glass

#include <iostream>#include <cstring>#include <cstdio>#include <algorithm>using namespace std;const int base = 10000, cap = 30;struct xnum {  int len, data[cap];  xnum() : len(0) {}  xnum(const xnum& v) : len(v.len) { memcpy(data, v.data, len * sizeof *data); }  xnum(int v) : len(0) { for (; v > 0; v /= base) data[len++] = v % base; }  xnum& operator=(const xnum& v) { len = v.len; memcpy(data, v.data, len * sizeof *data); return *this; }  int& operator[](int index) { return data[index]; }  int operator[](int index) const { return data[index]; } }; xnum operator+(const xnum& a, const xnum& b) {  xnum r; int i, c = 0;  for (i = 0; i < a.len || i < b.len || c > 0; i++) {  if (i < a.len) c += a[i];  if (i < b.len) c += b[i];  r[i] = c % base;  c /= base;  }  r.len = i;  return r; } ostream& operator<<(ostream& out, const xnum& v) { out << (v.len == 0 ? 0 : v[v.len - 1]);  for (int i = v.len - 2; i >= 0; i--) for (int j = base / 10; j > 0; j /= 10) out << v[i] / j % 10;  return out; }xnum f[3][4][70][200];int n;void display(){ while (cin>>n) { for (int v=1;v<=3*(n+1);v++) for (int i=0;i<=n;i++) for (int j=1;j<=3;j++) for (int k=1;k<=2;k++) f[k][j][i][v]=xnum(0); f[1][1][n][1]=xnum(1); for (int v=1;v<=3*(n+1);v++) for (int i=n;i>=0;i--) for (int j=1;j<=3;j++) for (int k=1;k<=2;k++) { if (j==1) { if (k==1) f[k][j][i][v]=f[k][j][i][v]+f[2][j][i+1][v-1]; if (k==2) f[k][j][i][v]=f[k][j][i][v]+f[1][j][i+1][v-1]+f[2][2][i][v-1]; } if (j==2) { if (k==1) f[k][j][i][v]=f[k][j][i][v]+f[2][j][i+1][v-1]+f[k][1][i][v-1]; if (k==2) f[k][j][i][v]=f[k][j][i][v]+f[1][j][i+1][v-1]+f[k][3][i][v-1]; } if (j==3) { if (k==1) f[k][j][i][v]=f[k][j][i][v]+f[2][j][i+1][v-1]+f[k][2][i][v-1]; if (k==2) f[k][j][i][v]=f[k][j][i][v]+f[1][j][i+1][v-1]; } } xnum ans; ans=xnum(0); for (int i=1;i<=3*(n+1);i++) ans=ans+f[2][1][0][i]+f[1][3][0][i]; cout<<ans<<endl; }}int main(){ display(); return 0;}