View Compilation Error

0_0_29020060_15371.cpp: In function 'void fun()':
0_0_29020060_15371.cpp:8:12: error: array must be initialized with a brace-enclosed initializer
  ll sum[0]=0;
            ^
0_0_29020060_15371.cpp:9:6: error: 'i' was not declared in this scope
  for(i=1;i<100005;i++)
      ^