foo.c: In function 'main':
foo.c:7:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
  scanf("%d %d",&m,&n);
  ^~~~~~~~~~~~~~~~~~~~
foo.c:14:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    scanf("%d",&a[i][j]);
    ^~~~~~~~~~~~~~~~~~~~
foo.c:6:2: warning: 'n' is used uninitialized in this function [-Wuninitialized]
  int a[m][n];
  ^~~
foo.c:6:2: warning: 'm' is used uninitialized in this function [-Wuninitialized]

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