c++ - 无法找到错误，但编译器给出以下消息:

Question

错误消息显示:
在函数void LCSlength(std::__cxx11::string, std::__cxx11::string, int, int)中

错误:

expression cannot be used as a function lookup[ i ][ j ] = max (lookup[i - 1] [ j ],lookup[ i ] [ j - 1 ]);

#define max 20

int lookup[max][max];

void LCSlength(string x,string y,int m,int n)
{
  for(int i = 1;i<=m;i++)
  {
    for(int j = 1;j<=n;j++)
    {
      if(x[i - 1] == y[j - 1])
       lookup[i][j] = lookup[i - 1][j - 1] + 1;
       else
        lookup[i][j] = max(lookup[i - 1][j], lookup[i][j - 1]);
    }
  }
}

Answer 1

使用std::max(lookup[i - 1][j], lookup[i][j - 1]);并将宏名称替换为maximum:

#define maximum 20
int lookup[maximum][maximum];