View Compilation Error

0_0_21598938_29114.cpp: In function 'bool dfs(int)':
0_0_21598938_29114.cpp:2:22: error: 'g' was not declared in this scope
  for (int i = 0; i < g[u].size(); i++) {
                      ^
0_0_21598938_29114.cpp:4:7: error: 'vis' was not declared in this scope
   if (vis[v]) continue;
       ^
0_0_21598938_29114.cpp:5:3: error: 'vis' was not declared in this scope
   vis[v] = 1;
   ^
0_0_21598938_29114.cpp:6:8: error: 'left' was not declared in this scope
   if (!left[v] || dfs(left[v])) {
        ^
0_0_21598938_29114.cpp: In function 'int hungary()':
0_0_21598938_29114.cpp:16:9: error: 'left' was not declared in this scope
  memset(left, 0, sizeof(left));
         ^
0_0_21598938_29114.cpp:16:30: error: 'memset' was not declared in this scope
  memset(left, 0, sizeof(left));
                              ^
0_0_21598938_29114.cpp:17:23: error: 'G' was not declared in this scope
  for (int i = 1; i <= G; i++) {
                       ^
0_0_21598938_29114.cpp:18:10: error: 'vis' was not declared in this scope
   memset(vis, 0, sizeof(vis));
          ^