foo.cc: In function 'int main()':
foo.cc:5:13: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'int*' [-Wformat=]
    5 |     scanf("%s %s",&a,&b);
      |            ~^     ~~
      |             |     |
      |             char* int*
      |            %d
foo.cc:5:16: warning: format '%s' expects argument of type 'char*', but argument 3 has type 'int*' [-Wformat=]
    5 |     scanf("%s %s",&a,&b);
      |               ~^     ~~
      |                |     |
      |                char* int*
      |               %d
foo.cc:6:12: warning: format '%s' expects argument of type 'char*', but argument 2 has type 'int' [-Wformat=]
    6 |   printf("%s\n",a+b);
      |           ~^    ~~~
      |            |     |
      |            char* int
      |           %d
foo.cc:5:10: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    5 |     scanf("%s %s",&a,&b);
      |     ~~~~~^~~~~~~~~~~~~~~

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