Language is C++

Read fileName and three integers from input. Open fileName as an output file. If the file fails to open, use cout to output fileName followed by ": error occurred while opening file.", and do not proceed to the code that writes to the file. Otherwise, for each integer read, write "\#" followed by the integer to the opened file. End each output with a newline and close the file. Ex: If the input is output.txt 381628 , then output.txt contains: \# 38 \# 16 \# 28