View Compilation Error

0_0_21990341_1534.cpp: In function 'void solve(int)':
0_0_21990341_1534.cpp:15:2: error: 'dp' was not declared in this scope
  dp[u][0] = v[u];
  ^
0_0_21990341_1534.cpp:18:24: error: 'nxt' was not declared in this scope
  for(int i=head[u];i;i=nxt[i]) {
                        ^
0_0_21990341_1534.cpp: In function 'int main()':
0_0_21990341_1534.cpp:45:6: error: 'dp' was not declared in this scope
   if(dp[0][0] < 0)puts("HAHAHAOMG");
      ^