foo.cc: In function 'int main()':
foo.cc:35:23: warning: 'd4' may be used uninitialized [-Wmaybe-uninitialized]
   35 |     printf("%.2lf",d4 * 100 / double(n));
      |                    ~~~^~~~~
foo.cc:7:21: note: 'd4' was declared here
    7 |     double d1,d2,d3,d4;
      |                     ^~
foo.cc:33:23: warning: 'd3' may be used uninitialized [-Wmaybe-uninitialized]
   33 |     printf("%.2lf",d3 * 100 / double(n));
      |                    ~~~^~~~~
foo.cc:7:18: note: 'd3' was declared here
    7 |     double d1,d2,d3,d4;
      |                  ^~
foo.cc:31:23: warning: 'd2' may be used uninitialized [-Wmaybe-uninitialized]
   31 |     printf("%.2lf",d2 * 100 / double(n));
      |                    ~~~^~~~~
foo.cc:7:15: note: 'd2' was declared here
    7 |     double d1,d2,d3,d4;
      |               ^~
foo.cc:29:23: warning: 'd1' may be used uninitialized [-Wmaybe-uninitialized]
   29 |     printf("%.2lf",d1 * 100 / double(n));
      |                    ~~~^~~~~
foo.cc:7:12: note: 'd1' was declared here
    7 |     double d1,d2,d3,d4;
      |            ^~

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