View Compilation Error

0_0_35718890_153.cpp: In function 'long long int C(int, int)':
0_0_35718890_153.cpp:10:25: error: 'long long int C(int, int)' redeclared as different kind of symbol
 long long C(int n, int m) {
                         ^
0_0_35718890_153.cpp:8:5: note: previous declaration 'int C [2000][2000]'
 int C[2000][2000];
     ^
0_0_35718890_153.cpp:13:18: error: 'fac' was not declared in this scope
     return 1ll * fac[n] * inv[fac[m]] % MOD * inv[fac[n - m]] % MOD;
                  ^
0_0_35718890_153.cpp:13:27: error: 'inv' was not declared in this scope
     return 1ll * fac[n] * inv[fac[m]] % MOD * inv[fac[n - m]] % MOD;
                           ^
0_0_35718890_153.cpp: In function 'int main()':
0_0_35718890_153.cpp:38:36: error: 'LL' was not declared in this scope
    S2[i][j] = (S2[i - 1][j - 1] + (LL)S2[i - 1][j] * j) % MOD;//注意溢出
                                    ^
0_0_35718890_153.cpp:38:39: error: expected ')' before 'S2'
    S2[i][j] = (S2[i - 1][j - 1] + (LL)S2[i - 1][j] * j) % MOD;//注意溢出
                                       ^