View Compilation Error

0_0_36813790_31368.cpp:8:20: error: 'v' has not been declared
 void add(int u,int,v,int dis){
                    ^
0_0_36813790_31368.cpp: In function 'void add(int, int, int, int)':
0_0_36813790_31368.cpp:10:21: error: 'v' was not declared in this scope
  e.nxt=head[u],e.to=v,e.d=dis,head[u]=tot;
                     ^
0_0_36813790_31368.cpp: In function 'void spfa()':
0_0_36813790_31368.cpp:16:13: error: 'o' was not declared in this scope
  memset(cnt,o,sizeof cnt);
             ^
0_0_36813790_31368.cpp: In function 'int main()':
0_0_36813790_31368.cpp:52:16: error: too few arguments to function 'void add(int, int, int, int)'
     add(i,v,dis);
                ^
0_0_36813790_31368.cpp:8:6: note: declared here
 void add(int u,int,v,int dis){
      ^
0_0_36813790_31368.cpp:55:22: error: could not convert 'spfa()' from 'void' to 'bool'
   printf("%s\n",spfa()?"winnable":"hopeless");
                      ^