foo.cc: In function 'int main()':
foo.cc:7:2: error: expected ',' or ';' before 'cin'
    7 |  cin>>y>>m>>d;
      |  ^~~
foo.cc:8:28: error: incompatible types in assignment of 'int' to 'int [13]'
    8 |  for(int i=1;i<m;i++)a+=a[i]
      |                            ^
foo.cc:10:11: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   10 |  if(y%4==0&&y%100!=0||y%400==0)
      |     ~~~~~~^~~~~~~~~~
foo.cc:11:11: error: lvalue required as increment operand
   11 |   if(m>2)a++;
      |           ^~

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