foo.c: In function 'main':
foo.c:4:13: error: 'n' undeclared (first use in this function)
    4 |  scanf("%d",n);
      |             ^
foo.c:4:13: note: each undeclared identifier is reported only once for each function it appears in
foo.c:7:14: error: 'j' undeclared (first use in this function)
    7 |          for(j=m-n;j>=0;j--,i++)
      |              ^
foo.c:7:29: error: 'i' undeclared (first use in this function)
    7 |          for(j=m-n;j>=0;j--,i++)
      |                             ^
foo.c:7:28: warning: left-hand operand of comma expression has no effect [-Wunused-value]
    7 |          for(j=m-n;j>=0;j--,i++)
      |                            ^
foo.c:11:33: error: expected ';' before '}' token
   11 |                   printf("%d",i)
      |                                 ^
      |                                 ;
......
   14 |          }
      |          ~                       
foo.c:3:6: warning: unused variable 'n\U0000ff0ci' [-Wunused-variable]
    3 | {int n，i=0,m;
      |      ^~~~

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