View Compilation Error

0_0_23241033_23907.cpp: In function 'int main()':
0_0_23241033_23907.cpp:17:18: error: 'n' was not declared in this scope
   for(int i=1;i<=n;++i) scanf("%d",a+i);
                  ^
0_0_23241033_23907.cpp:18:18: error: 'n' was not declared in this scope
   for(int i=1;i<=n;++i) scanf("%d",b+i);
                  ^
0_0_23241033_23907.cpp:22:18: error: 'n' was not declared in this scope
   for(int i=1;i<=n;++i) {
                  ^
0_0_23241033_23907.cpp:38:18: error: 'n' was not declared in this scope
   for(int i=1;i<=n;++i) ans=ans^a[i];
                  ^