src.c: In function 'main':
src.c:8:9: error: 'a' undeclared (first use in this function)
a=1；
^
src.c:8:9: note: each undeclared identifier is reported only once for each function it appears in
src.c:8:9: error: stray '\357' in program
src.c:8:9: error: stray '\274' in program
src.c:8:9: error: stray '\233' in program
src.c:9:9: error: expected ';' before 'for'
for(n=b;n>=1;n--)
^