step1: Create a C program file, such as vi mul.c
step2: Write the C program code you want to write, such as
step3: After writing the program, press the ESC key, then press shift+: (colon), enter wq, and click enter
step4: Compile the program, enter the command gcc -o mul mul.c
step5: Run the program and enter the command ./mul
So far, a C language program runs successfully