foo.cc: In function 'int main()':
foo.cc:22:61: warning: format '%d' expects argument of type 'int*', but argument 4 has type 'int (*)[20]' [-Wformat=]
   scanf("%d%s%d%d",&ar[i].a,ar[i].name,&ar[i].haoma,&ar[i].b);
                                        ~~~~~~~~~~~~         ^
foo.cc:22:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   scanf("%d%s%d%d",&ar[i].a,ar[i].name,&ar[i].haoma,&ar[i].b);
   ~~~~~^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

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