View Compilation Error

0_0_18020029_25248.cpp: In function 'int main()':
0_0_18020029_25248.cpp:8:5: error: 'Mat' was not declared in this scope
     Mat A(3,3),F(1,3);  
     ^
0_0_18020029_25248.cpp:10:5: error: 'mod' was not declared in this scope
     mod = 200907;  
     ^
0_0_18020029_25248.cpp:18:9: error: 'A' was not declared in this scope
         A.clear();  
         ^
0_0_18020029_25248.cpp:19:9: error: 'F' was not declared in this scope
         F.clear(2);F.s[0][0] = 2;  
         ^