View Compilation Error

0_0_15769758_18607.cpp: In function 'int main()':
0_0_15769758_18607.cpp:9:10: error: 'c2' was not declared in this scope
   a[i]=0;c2[i]=0;
          ^
0_0_15769758_18607.cpp:42:33: error: 'c2' was not declared in this scope
                                 c2[d]+=a[j];                             
                                 ^
0_0_15769758_18607.cpp:48:30: error: 'c2' was not declared in this scope
                         a[j]=c2[j];
                              ^