foo.cc: In function 'int main()':
foo.cc:26:16: error: 'nt' was not declared in this scope; did you mean 'n'?
   26 |     for (int i=nt; i>=0; i--)
      |                ^~
      |                n
foo.cc:27:18: error: 'na' was not declared in this scope; did you mean 'nan'?
   27 |       for (int j=na; j>=0; j--) {
      |                  ^~
      |                  nan
foo.cc:28:21: error: 't' was not declared in this scope
   28 |         int x=min(i+t[k], nt), y=min(j+a[k], na);
      |                     ^
foo.cc:29:9: error: 'opt' was not declared in this scope
   29 |         opt[x][y]=min(opt[x][y], opt[i][j]+w[k]);
      |         ^~~

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