View Compilation Error

0_0_27120096_8192.cpp: In function 'int main()':
0_0_27120096_8192.cpp:142:5: error: redefinition of 'int main()'
 int main()
     ^
0_0_27120096_8192.cpp:108:5: note: 'int main()' previously defined here
 int main()
     ^
0_0_27120096_8192.cpp:144:16: error: 'first' was not declared in this scope
         memset(first,-1,sizeof(first));
                ^
0_0_27120096_8192.cpp:145:16: error: 'nex' was not declared in this scope
         memset(nex,-1,sizeof(nex));
                ^
0_0_27120096_8192.cpp:146:9: error: 'cc' was not declared in this scope
         cc=0;
         ^
0_0_27120096_8192.cpp:153:25: error: 'add_edge' was not declared in this scope
         add_edge(u,v,c,w);
                         ^
0_0_27120096_8192.cpp:155:23: error: 'Min_Cost_Flow' was not declared in this scope
     Min_Cost_Flow(s, t);
                       ^