foo.cc: In function 'int main()':
foo.cc:13:17: warning: iteration 2000004 invokes undefined behavior [-Waggressive-loop-optimizations]
   13 |         if(arr[i]=='W')
      |            ~~~~~^
foo.cc:12:18: note: within this loop
   12 |     for(int i=1;i<=len;i++){
      |                 ~^~~~~
foo.cc:34:17: warning: iteration 2000004 invokes undefined behavior [-Waggressive-loop-optimizations]
   34 |         if(arr[i]=='W')
      |            ~~~~~^
foo.cc:33:18: note: within this loop
   33 |     for(int i=1;i<=len;i++){
      |                 ~^~~~~

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