foo.c: In function 'main':
foo.c:10:34: error: 'y' undeclared (first use in this function)
10 | scanf("%d%d",&x,&y);
| ^
foo.c:10:34: note: each undeclared identifier is reported only once for each function it appears in
foo.c:13:33: error: 'a' undeclared (first use in this function)
13 | a[i]=2*x;
| ^
foo.c:11:19: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
11 | if(x==y)
| ^
foo.c:16:19: warning: suggest explicit braces to avoid ambiguous 'else' [-Wdangling-else]
16 | if(x-2==y)
| ^
foo.c:7:15: warning: unused variable 'y\U0000ff0ca' [-Wunused-variable]
7 | int x,y,a[20000];
| ^~~~
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