foo.cc: In function 'int main()':
foo.cc:7:8: warning: unused variable 'j' [-Wunused-variable]
    7 |  int i,j,len,t1,t2,t3,t4,t5,T,flag,sum1,sum2;
      |        ^
foo.cc:9:7: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
    9 |  scanf("%d",&T);
      |  ~~~~~^~~~~~~~~
foo.cc:12:8: warning: ignoring return value of 'int scanf(const char*, ...)', declared with attribute warn_unused_result [-Wunused-result]
   12 |   scanf("%s",str);
      |   ~~~~~^~~~~~~~~~

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