11511 - Frieze Patterns/frieze.3.cpp

   1 /*
   2   Accepted
   3  */
   4 #include<iostream>
   5 #include<cstdio>
   6 #include<vector>
   7 using namespace std;
   8
   9 int f[1005][1005];
  10
  11 int main(){
  12   //assert(freopen("frieze.in", "r", stdin) != NULL);
  13   int n, row, col;
  14   while (cin >> n >> row >> col && n){
  15
  16     for (int i=1; i<=n; ++i) cin >> f[i][1];
  17
  18     for (int j=1; j<=n+1; ++j) f[1][j] = f[n][j] = 1;
  19
  20     for (int j=2; j<=n+1; ++j)
  21       for (int i=2; i<n; ++i)
  22         f[i][j] = (f[i+1][j-1]*f[i-1][j]+1)/f[i][j-1];
  23
  24
  25     /*
  26     for (int i=1; i<=n; ++i){
  27       for (int j=1; j<=n+1; ++j)
  28         printf("%3d ", f[i][j]);
  29       puts("");
  30     }
  31     */
  32     if (col % (n+1) == 0) col = n+1;
  33     else col %= (n+1);
  34
  35     cout << f[row][col] << endl;
  36   }
  37   return 0;
  38 }