foo.cc: In function 'bool cmp(node, node)':
foo.cc:17:27: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
 { return a.a<b.a||a.a==b.a&&a.b<b.b;}
                   ~~~~~~~~^~~~~~~~~
foo.cc: In function 'int main()':
foo.cc:20:20: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
  scanf("%d%d",&n,&m);
               ~~   ^
foo.cc:20:20: warning: format '%d' expects argument of type 'int*', but argument 3 has type 'long long int*' [-Wformat=]
foo.cc:23:23: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
    scanf("%d",&a[i][j]);
               ~~~~~~~~^
foo.cc:26:23: warning: format '%d' expects argument of type 'int*', but argument 2 has type 'long long int*' [-Wformat=]
    scanf("%d",&b[i][j]);
               ~~~~~~~~^
foo.cc:57:18: warning: suggest parentheses around '&&' within '||' [-Wparentheses]
   while(j<=q[i].x&&j<k||i==cnt)
         ~~~~~~~~~^~~~~
foo.cc:59:50: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
    if(i==1) printf("%d\n",j*q[i].dot.a+q[i].dot.b);
                           ~~~~~~~~~~~~~~~~~~~~~~~^
foo.cc:60:80: warning: format '%d' expects argument of type 'int', but argument 2 has type 'long long int' [-Wformat=]
    else  printf("%d\n",max(j*q[i-1].dot.a+q[i-1].dot.b,j*q[i].dot.a+q[i].dot.b));
                        ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^
foo.cc:42:9: warning: unused variable 'x' [-Wunused-variable]
  double x;
         ^
foo.cc:20:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d%d",&n,&m);
  ~~~~~^~~~~~~~~~~~~~
foo.cc:23:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&a[i][j]);
    ~~~~~^~~~~~~~~~~~~~~
foo.cc:26:9: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&b[i][j]);
    ~~~~~^~~~~~~~~~~~~~~

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