View Compilation Error

0_0_25361442_13579.cpp: In function 'int main()':
0_0_25361442_13579.cpp:12:10: error: missing template arguments before '[' token
      rank[i]=(i+1)*i/2;
          ^
0_0_25361442_13579.cpp:17:19: error: missing template arguments before '[' token
   cnt[i]=(sum[rank[f[i]-1]]-sum[i-f[i]-1]+mod)%mod;
                   ^