View Compilation Error

0_0_33700788_8871.cpp: In function 'int main(int, const char**)':
0_0_33700788_8871.cpp:75:10: error: 'u' was not declared in this scope
        g[u][v]--,g[v][u]--;
          ^
0_0_33700788_8871.cpp:75:13: error: 'v' was not declared in this scope
        g[u][v]--,g[v][u]--;
             ^