View Compilation Error

0_0_22235414_7363.cpp:7:11: error: '_int64' does not name a type
   typedef _int64 LL;
           ^
0_0_22235414_7363.cpp:28:2: error: 'LL' does not name a type
  LL Extended_Euclid(LL a,LL b,LL &x,LL &y)
  ^
0_0_22235414_7363.cpp:36:2: error: 'LL' does not name a type
  LL inv(LL a,LL n)//计算模na的逆，若不存在逆返?1
  ^
0_0_22235414_7363.cpp: In function 'int Det(int)':
0_0_22235414_7363.cpp:63:50: error: 'inv' was not declared in this scope
              int mut=(mat[j][i]*inv(mat[i][i],MOD))%MOD;
                                                  ^