View Compilation Error

0_0_29996742_1787.cpp: In function 'int main()':
0_0_29996742_1787.cpp:15:15: error: 'x' was not declared in this scope
         while(x<n&&y<n) {
               ^
0_0_29996742_1787.cpp:15:20: error: 'y' was not declared in this scope
         while(x<n&&y<n) {
                    ^