foo.c: In function 'main':
foo.c:22:12: error: expected '(' before '{' token
         for{j=i-1;j>=2;j--)
            ^
foo.c:22:20: warning: statement with no effect [-Wunused-value]
         for{j=i-1;j>=2;j--)
                   ~^~~
foo.c:22:27: error: expected ';' before ')' token
         for{j=i-1;j>=2;j--)
                           ^
foo.c:22:27: error: expected statement before ')' token
foo.c:37:1: error: expected declaration or statement at end of input
 }
 ^