foo.cc: In function 'bool hw(long long int)':
foo.cc:14:20: warning: unused variable 'j' [-Wunused-variable]
   14 |  long long k,len=0,j;
      |                    ^
foo.cc: In function 'int main()':
foo.cc:35:10: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
   35 |  scanf("%d%d",&a,&b);
      |         ~^    ~~
      |          |    |
      |          int* long long int*
      |         %lld
foo.cc:35:12: warning: format '%d' expects argument of type 'int*', but argument 3 has type 'long long int*' [-Wformat=]
   35 |  scanf("%d%d",&a,&b);
      |           ~^     ~~
      |            |     |
      |            int*  long long int*
      |           %lld
foo.cc:45:13: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
   45 |    printf("%d\n",i);
      |            ~^    ~
      |             |    |
      |             int  long long int
      |            %lld
foo.cc:35:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   35 |  scanf("%d%d",&a,&b);
      |  ~~~~~^~~~~~~~~~~~~~

Found 10 testcases.
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