Question

当使用扫描功能进行输入时,会给出两个输入。

首先,我是一个 python 程序程序员, 试图学习 C。我试图寻找为什么会发生这种情况, 但没有发现任何结果。下面的代码是:

#include <stdio.h>

int main() {

    int age;

    printf("Enter your age: ");
    scanf("%d
", &age);
    printf("Your age is %d
", age);
    
    return 0;
}

在 VSCode 运行和调试时, 这就是我得到的:

Enter your age: 23
12
Your age is 23

任何帮助都将不胜感激。

Answer 1

The is unnecessary in the scanf format string. It tells scanf to continue reading any number of whitespace characters, until it finds the next non-whitespace character.

代之以使用 scanf ("%d", & amp;age);

Answer 2

printf 语句:此输出输出到控制台的即时“ 输入您的年龄 : ” 。

scanf Statement: This is where the issue lies. The format string "%d " tells scanf to expect an integer followed by a newline character.

The in the scanf format string causes scanf to wait for a newline character after reading the integer. This means that scanf will not complete until you press Enter twice: once after entering the integer and once more for the newline.

校正使用率

#include <stdio.h>

int main() {
    int age;
    printf("Enter your age: ");
    scanf("%d", &age);
    printf("Your age is %d
", age);
    
    return 0;
}

printf 语句:输出“输入年龄:”到控制台。

scanf 语句: 格式字符串 “%d”告诉 scanf 期待一个单整数。这将在不等待额外新行字符的情况下正确工作。

友情链接