C++中printf格式化输出整理_c++ printf double

目录

printf格式字符串

实际测试结果

参考资料

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printf格式字符串

 

 

 

 

 

 

 

 

 

 

 

 

 

 

实际测试结果

#include <iostream>
#include <string.h>
 
int main()
{
	char c;
	int i1 = -78;
	int i2 = 78;
	unsigned int u = 78;
	long l = 1234567890;
	long long ll = 1234567890123456789;
	float f1 = 3.123456;
	float f2 = 3.100000;
	double x = 123.12345678912345;
	std::string s = "Hello,world";
	c = '\x41';
	
	printf("i1 = %d\n", i1); //%d,十进制int,i1 = -78
	
	printf("i2 = %d\n", i2); //%d,十进制int,i2 = 78
	
	printf("i1 = %i\n", i1); //%d,十进制int,i1 = -78
	
	printf("i2 = %d\n", i2); //%d,十进制int,i2 = 78
	
	printf("u = %u\n", u); //%u,无符号十进制int，u = 78
 
	printf("i2 = %d%%\n", i2); //%d,十进制int,%%输出%号，i2 = 78%
 
	printf("i1 = %o\n", i1); //%o，八进制int，不输出o，i1 = 37777777662
 
	printf("i2 = %o\n", i2); //%o，八进制int，不输出o，i2 = 116
 
	printf("i2 = %#o\n", i2); //%o，八进制int，#输出o，i2 = o116
	
	printf("i1 = %x\n", i1); //%x，十六进制int，不输出0x，i1 = ffffffb2
 
	printf("i2 = %x\n", i2); //%x，十六进制int，不输出0x，i2 = 4e
 
	printf("i2 = %X\n", i2); //%X，十六进制int，不输出0X，i2 = 4E
	
	printf("i2 = %#x\n", i2); //%x，十六进制int，#输出0x，i2 = 0x4e
	
	printf("i2 = %08d\n", i2); //%d,十进制int,8表示输出最小宽度，超过按实际位数，不足的左边补0，i2 = 00000078
 
	printf("i2 = %+8d\n", i2); //%d,十进制int,+输出+号，8表示输出最小宽度，超过按实际位数，不足的左边补空格，i2 =      +78
 
	printf("i2 = %-8d\n", i2); //%d,十进制int,-左对齐，8表示输出最小宽度，超过按实际位数，不足的右边补空格，i2 = 78     
 
	printf("i1 = % d\n", i1); //%d,十进制int,空格表示输出值为正时加空格，为负时加-号，i1 = -78
 
	printf("i2 = % d\n", i2); //%d,十进制int,空格表示输出值为正时加空格，为负时加-号，i2 =  78
 
	printf("l = %ld\n", l); //%ld,十进制long,l = 1234567890
	
	printf("ll = %lld\n", ll); //%lld,十进制long long,ll = 1234567890123456789
 
	printf("f1 = %f\n", f1); //%f,float,有效数字是7位，f1 = 3.123456
	
	printf("f1 = %6.10f\n", f1); //%f,float,有效数字是7位，最少输出6位，小数点后有8位，超出范围，f1 = 3.1234560013
 
	printf("f1 = %a\n", f1); //%a,十六进制和p-记数法，float,有效数字是7位，f1 = 0x1.8fcd680000000p+1
 
	printf("f1 = %A\n", f1); //%A,十六进制和P-记数法，float,有效数字是7位，f1 = 0x1.8Fcd680000000P+1
	
	printf("f1 = %e\n", f1); //%e,指数e-记数法，float,有效数字是7位，f1 = 3.123456e+00
 
	printf("f2 = %E\n", f2); //%E,指数E-记数法，float,有效数字是7位，f2 = 3.100000E+00
	
	printf("f2 = %g\n", f2); //%g,不显示无意义的0，float,有效数字是7位，f2 = 3.1
 
	printf("x = %lf\n", x); //%x,double，x = 123.123457
 
	printf("x = %10.14lf\n", x); //%x,double，x = 123.12345678912345
	
	printf("c = %c\n", c); //%c,char,c = A
	
	printf("c = %x\n", c); //%x,以十六进制输出字符ascll码,c = 41
 
	printf("s = %s\n", s.c_str()); //%s,输出字符串,s = Hello,world
 
	printf("s = %6.9s\n", s.c_str()); //%s,输出字符串,最多输出9个字符，s = Hello,wor
	
	printf("s = %10.9s\n", s.c_str()); //%s,输出字符串,最多输出9个字符，不足左边补空格，s =  Hello,wor
 
	system("pause");
	return 0;
}

参考资料

【C++】printf格式化输出：https://blog.csdn.net/u013066730/article/details/84243819

C++---常用printf输出格式：https://blog.csdn.net/qq_40951833/article/details/103104812