foo.cpp: In function 'int main()':
foo.cpp:66:7: error: redeclaration of 'int o1'
   int o1=get_match(x);
       ^
foo.cpp:61:33: error: 'int o1' previously declared here
   int x=id[px][py],y=match[x],t,o1=0,o2=0;
                                 ^
foo.cpp:76:7: error: redeclaration of 'int o2'
   int o2=get_match(x);
       ^
foo.cpp:61:38: error: 'int o2' previously declared here
   int x=id[px][py],y=match[x],t,o1=0,o2=0;
                                      ^