View Compilation Error

0_0_32983379_6299.cpp: In function 'int solve(int)':
0_0_32983379_6299.cpp:67:22: error: 'b' was not declared in this scope
         int u=a[i],v=b[i];
                      ^
0_0_32983379_6299.cpp: In function 'int main()':
0_0_32983379_6299.cpp:90:46: error: 'b' was not declared in this scope
         for(i = 1;i <= n;i++) cin >> a[i] >> b[i];
                                              ^