Consider below simple program in C. The program reads an integer using scanf(), then reads a string using fgets().
x = 10, str =
The problem with above code is scanf() reads an integer and leaves a newline character in buffer. So fgets() only reads newline and the string “test” is ignored by the program.
The similar problem occurs when scanf() is used in a loop.
a b q
......Enter q to quit...... Enter a character a Enter a character Enter a character b Enter a character Enter a character q
We can notice that above program prints an extra “Enter a character” followed by an extra new line. This happens because every scanf() leaves a newline character in buffer that is read by next scanf.
How to solve above problem?
- We can make scanf() to read a new line by using an extra “\n”, i.e., scanf(“%d\n”, &x) . In fact scanf(“%d “, &x) also works (Note extra space).
- We can add a getchar() after scanf() to read an extra newline.
This article is contributed by Dheeraj Gupta. Please write comments if you find anything incorrect, or you want to share more information about the topic discussed above
- Use of & in scanf() but not in printf()
- Cin-Cout vs Scanf-Printf
- Why "&" is not used for strings in scanf() function?
- Return values of printf() and scanf() in C/C++
- scanf() and fscanf() in C - Simple Yet Poweful
- Inbuilt library functions for user Input | scanf, fscanf, sscanf, scanf_s, fscanf_s, sscanf_s
- Problem Solving on Storage Classes and Scoping of Variables
- Dividing a Large file into Separate Modules in C/C++, Java and Python
- C program to store Student records as Structures and Sort them by Name
- Similarities and Differences between Ruby and C language
- Program to copy the contents of one array into another in the reverse order
- Interesting facts about C Language
- Program to Reverse a String using Pointers
- Difference between Structure and Array in C