foo.cc: In function 'void DFS(std::vector<std::vector<int> >, int, int, int, int, int, int, int&, int)':
foo.cc:34:54: error: 'maxans' was not declared in this scope
    DFS(Map,nextx,nexty,res+Map[nextx][nexty],ans,n,m,maxans,1);
                                                      ^~~~~~
foo.cc:34:54: note: suggested alternative: 'ans'
    DFS(Map,nextx,nexty,res+Map[nextx][nexty],ans,n,m,maxans,1);
                                                      ^~~~~~
                                                      ans
foo.cc:40:12: error: 'nextx' was not declared in this scope
    DFS(Map,nextx,nexty,res,ans+Map[x][ry],n,m,maxans,0);
            ^~~~~
foo.cc:40:18: error: 'nexty' was not declared in this scope
    DFS(Map,nextx,nexty,res,ans+Map[x][ry],n,m,maxans,0);
                  ^~~~~
foo.cc:40:47: error: 'maxans' was not declared in this scope
    DFS(Map,nextx,nexty,res,ans+Map[x][ry],n,m,maxans,0);
                                               ^~~~~~
foo.cc:40:47: note: suggested alternative: 'ans'
    DFS(Map,nextx,nexty,res,ans+Map[x][ry],n,m,maxans,0);
                                               ^~~~~~
                                               ans
foo.cc:42:18: error: 'dy' was not declared in this scope
   else if(dx<n&&(dy>=m||Map[dx][y]>Map[x][ry]){
                  ^~
foo.cc:42:18: note: suggested alternative: 'dx'
   else if(dx<n&&(dy>=m||Map[dx][y]>Map[x][ry]){
                  ^~
                  dx
foo.cc:42:47: error: expected ')' before '{' token
   else if(dx<n&&(dy>=m||Map[dx][y]>Map[x][ry]){
                                               ^
foo.cc:45:2: error: expected primary-expression before '}' token
  }
  ^

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