View Compilation Error

0_0_14721227_32734.cpp:44:1: error: expected unqualified-id before numeric constant
 2120
 ^
0_0_14721227_32734.cpp: In function 'int find(int)':
0_0_14721227_32734.cpp:52:18: error: 'f' was not declared in this scope
     return  x == f[x] ? x : f[x] = find(f[x]);
                  ^
0_0_14721227_32734.cpp: In function 'int main()':
0_0_14721227_32734.cpp:55:5: error: redefinition of 'int main()'
 int main (){
     ^
0_0_14721227_32734.cpp:22:5: note: 'int main()' previously defined here
 int main (){
     ^
0_0_14721227_32734.cpp:60:34: error: 'f' was not declared in this scope
         for(i = 0; i <= N; i ++) f[i] = i;
                                  ^
0_0_14721227_32734.cpp:71:18: error: 'f' was not declared in this scope
             else f[fx] = fy;
                  ^