View Compilation Error

0_0_14808114_28356.cpp: In function 'void dfs(int, int, int, double)':
0_0_14808114_28356.cpp:53:24: error: 'y1' was not declared in this scope
                 dfs(x1,y1,fight-1,distance+(1.0*abs(str[x][y]-str[x1][y1]))/fight);
                        ^