foo.c:2:1: warning: return type defaults to 'int' [-Wimplicit-int]
    2 | Shan(int a[500][500],int m,int n)
      | ^~~~
foo.c: In function 'main':
foo.c:26:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   26 |    scanf("%d",&a[i][j]);
      |    ^~~~~~~~~~~~~~~~~~~~
foo.c:25:3: warning: 'n' is used uninitialized in this function [-Wuninitialized]
   25 |   for(j=0 ; j<n ; j++)
      |   ^~~
foo.c:28:4: warning: 'm' is used uninitialized in this function [-Wuninitialized]
   28 |  k=Shan(a,m,n);
      |    ^~~~~~~~~~~
foo.c:22:26: warning: 'i' may be used uninitialized in this function [-Wmaybe-uninitialized]
   22 |  int a[500][500]={0},m,n,i,j,k;
      |                          ^

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