foo.cc:3:1: error: expected initializer before 'using'
 using namespace std;
 ^~~~~
foo.cc: In function 'int main()':
foo.cc:10:24: error: 'b' was not declared in this scope
         scanf("%d %d",&b[i],&a[i]);
                        ^
foo.cc:22:19: error: 'b' was not declared in this scope
                 x=b[j];
                   ^
foo.cc:28:20: error: 'b' was not declared in this scope
                 if(b[j]>b[j+1])
                    ^
foo.cc:38:11: error: 'h' was not declared in this scope
     for(i=h;a[i]==a[i+1];i++)
           ^
foo.cc:42:24: error: 'h' was not declared in this scope
     printf("%d %d\n",a[h],h);
                        ^
foo.cc:45:26: error: 'b' was not declared in this scope
         printf("%d %d\n",b[i],a[i]);
                          ^
foo.cc:7:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
     scanf("%d %d",&n,&m);
     ~~~~~^~~~~~~~~~~~~~~

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