foo.c: In function 'main':
foo.c:9:13: error: expected identifier or '(' before 'int'
    9 | for(int i=a,int j=b int o=0;a<=b;o==o+a,o++)
      |             ^~~
foo.c:9:34: error: 'o' undeclared (first use in this function)
    9 | for(int i=a,int j=b int o=0;a<=b;o==o+a,o++)
      |                                  ^
foo.c:9:34: note: each undeclared identifier is reported only once for each function it appears in
foo.c:9:40: warning: left-hand operand of comma expression has no effect [-Wunused-value]
    9 | for(int i=a,int j=b int o=0;a<=b;o==o+a,o++)
      |                                        ^
foo.c:10:1: error: expected expression before 'else'
   10 | else for(int i=a,int j=b int o=0;a<=b;o==o+a,o++)
      | ^~~~
foo.c:9:9: warning: unused variable 'i' [-Wunused-variable]
    9 | for(int i=a,int j=b int o=0;a<=b;o==o+a,o++)
      |         ^

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