foo.cc: In function 'int main()':
foo.cc:23:22: error: 'f' was not declared in this scope
   23 |         else if(j==i)f[i][j]=min(min(F[i+1][j],F[i+1][j+1]),F[i+1][0])+a[i][j];
      |                      ^
foo.cc:24:27: error: 'f' was not declared in this scope
   24 |         else if(j>0&&j<i) f[i][j]=min(F[i+1][j],F[i+1][j+1])+a[i][j];
      |                           ^
foo.cc:8:23: warning: unused variable 'k' [-Wunused-variable]
    8 |         long n, i, j, k, tmp, x1, x2;
      |                       ^
foo.cc:8:26: warning: unused variable 'tmp' [-Wunused-variable]
    8 |         long n, i, j, k, tmp, x1, x2;
      |                          ^~~
foo.cc:8:31: warning: unused variable 'x1' [-Wunused-variable]
    8 |         long n, i, j, k, tmp, x1, x2;
      |                               ^~
foo.cc:8:35: warning: unused variable 'x2' [-Wunused-variable]
    8 |         long n, i, j, k, tmp, x1, x2;
      |                                   ^~

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