foo.c: In function 'main':
foo.c:20:11: warning: passing argument 1 of 'putchar' makes integer from pointer without a cast [-Wint-conversion]
   20 |   putchar("\n");
      |           ^~~~
      |           |
      |           char *
In file included from /usr/include/stdio.h:864,
                 from foo.c:1:
/usr/include/x86_64-linux-gnu/bits/stdio.h:82:14: note: expected 'int' but argument is of type 'char *'
   82 | putchar (int __c)
      |          ~~~~^~~
foo.c:6:2: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    6 |  scanf("%d",&M);
      |  ^~~~~~~~~~~~~~
foo.c:9:5: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
    9 |     scanf("%d",&n);
      |     ^~~~~~~~~~~~~~
foo.c:12:4: warning: ignoring return value of 'scanf', declared with attribute warn_unused_result [-Wunused-result]
   12 |    scanf("%d",&a[j]);
      |    ^~~~~~~~~~~~~~~~~

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