/in/foo.cc: In function 'int main()':
/in/foo.cc:64:9: error: 'de' was not declared in this scope
         de[a[i].col]++; //记录颜色
         ^~
/in/foo.cc:66:31: error: 'de' was not declared in this scope
     for(int i=1;i<=20;i++) if(de[i]) m=i; //求最大颜色编号
                               ^~