foo.c: In function 'main':
foo.c:4:9: warning: unused variable 'j' [-Wunused-variable]
 int n,m,j;
         ^
foo.c:5:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&n);
 ^~~~~~~~~~~~~~
foo.c:8:1: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
 scanf("%d",&t); 
 ^~~~~~~~~~~~~~

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