The meaning of %.2s in C language
In the formatted output function (such as printf()) of C language, "%.2s" means:
- %: Format specifier, indicating that the data will be output in a specific format.
- .: Precision indicator, indicating the length of the output string.
- 2: Specify the length of the output string to be 2 characters.
- s: Specify the output data type as string.
Therefore, the "%.2s" format specifier means to output a string of 2 characters in length. If you want to output a string of 10 characters in length, you can use the "%.10s" format specifier. If you want to output a string with no length limit, you can use the "%s" format specifier.
Example:
#include <stdio.h> int main() { char str[] = "Hello"; printf("输出长度为 2 个字符的字符串:%.2s\n", str); printf("输出长度为 10 个字符的字符串:%.10s\n", str); printf("输出没有长度限制的字符串:%s\n", str); return 0; }
Output:
<code>输出长度为 2 个字符的字符串:He 输出长度为 10 个字符的字符串:Hello 输出没有长度限制的字符串:Hello</code>
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