View Compilation Error

0_0_29254816_30121.c: In function 'main':
0_0_29254816_30121.c:19:17: error: 'c' undeclared (first use in this function)
                 c++;
                 ^
0_0_29254816_30121.c:19:17: note: each undeclared identifier is reported only once for each function it appears in