View Compilation Error

0_0_16399258_12823.cpp:9:16: error: '::main' must return 'int'
 long long main()
                ^
0_0_16399258_12823.cpp: In function 'int main()':
0_0_16399258_12823.cpp:22:13: error: 'prlong' was not declared in this scope
             prlong longf("The data have been tampered with!\n");
             ^
0_0_16399258_12823.cpp:36:13: error: 'prlong' was not declared in this scope
             prlong longf("The data have been tampered with!\n");
             ^
0_0_16399258_12823.cpp:38:13: error: 'prlong' was not declared in this scope
             prlong longf("It seems to have no problem.\n");
             ^