/in/foo.cc: In function 'int main()':
/in/foo.cc:63:21: error: 'amp' was not declared in this scope
  while(scanf("%d", &ch[1])!=EOF){
                     ^~~
/in/foo.cc:63:24: error: expected ')' before ';' token
  while(scanf("%d", &ch[1])!=EOF){
                        ^
/in/foo.cc:63:2: warning: this 'while' clause does not guard... [-Wmisleading-indentation]
  while(scanf("%d", &ch[1])!=EOF){
  ^~~~~
/in/foo.cc:63:25: note: ...this statement, but the latter is misleadingly indented as if it is guarded by the 'while'
  while(scanf("%d", &ch[1])!=EOF){
                         ^~
/in/foo.cc:63:30: error: expected ';' before ')' token
  while(scanf("%d", &ch[1])!=EOF){
                              ^
/in/foo.cc:63:29: warning: statement has no effect [-Wunused-value]
  while(scanf("%d", &ch[1])!=EOF){
                         ~~~~^