View Compilation Error

0_0_25310244_27467.cpp: In function 'int getvalue(std::string)':
0_0_25310244_27467.cpp:9:5: error: '_int64' was not declared in this scope
     _int64 result=0;
     ^
0_0_25310244_27467.cpp:18:13: error: 'result' was not declared in this scope
             result=result*16+t;
             ^
0_0_25310244_27467.cpp:22:13: error: 'result' was not declared in this scope
             result=result*16+t;
             ^
0_0_25310244_27467.cpp:26:24: error: 'result' was not declared in this scope
     return str[0]=='-'?result*-1:result;
                        ^
0_0_25310244_27467.cpp: At global scope:
0_0_25310244_27467.cpp:29:12: error: '_int64' was not declared in this scope
 string fun(_int64 a){
            ^
0_0_25310244_27467.cpp:29:21: error: expected ',' or ';' before '{' token
 string fun(_int64 a){
                     ^