foo.cc: In function 'int main()':
foo.cc:7:17: warning: unused variable 'c' [-Wunused-variable]
     int n,i,a,b,c;
                 ^
foo.cc: At global scope:
foo.cc:16:5: error: expected unqualified-id before 'if'
     if(b<=c)
     ^~
foo.cc:18:5: error: expected unqualified-id before 'return'
     return 0;
     ^~~~~~
foo.cc:19:1: error: expected declaration before '}' token
 }
 ^

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