View Compilation Error

0_0_5377808_2075.c: In function `main':
0_0_5377808_2075.c:10: error: syntax error before '/' token
0_0_5377808_2075.c:20: error: `ch' undeclared (first use in this function)
0_0_5377808_2075.c:20: error: (Each undeclared identifier is reported only once
0_0_5377808_2075.c:20: error: for each function it appears in.)