C语言编程学习课件 (14).pdf

Programming In CProgramming In C Programming In CProgramming In C According to the five characteristics of the algorithm,a complete program must have output.The default standard output device is the displayer.There is no output statement in C,so it needs to call the output function in the standard library function to display data and information.Common output functions are:printf(),putchar(),puts().These library functions used in a program need to include the header file stdio.h.Programming In CProgramming In C The prototype for printf()is int printf(const char*control_string,.);printf(“a=%4d,b=%.2fn“,10 ,3.5);“a=10,b=3.50n”Programming In CProgramming In C printf(“The total of 6 and 5 is%d.”,6+5);printf()function allows to expression and display the results.%d:control string.output a integer expression Code Format%a Hexadecimal output in the form 0 xh.hhhhp+d(C99 only).%A Hexadecimal output in the form 0Xh.hhhhP+d(C99 only).%c Character.%d Signed decimal integers.%i Signed decimal integers.%e Scientific notation(lowercase e).%E Scientific notation(uppercase E).%f Decimal floating point.printf()functions format specifiers(1)printf()functions format specifiers(2)Code Format%g Uses%e or%f,whichever is shorter.%G Uses%E or%F,whichever is shorter.%o Unsigned octal.%s String of characters.%u Unsigned decimal integers.%x Unsigned hexadecimal(lowercase letters).%X Unsigned hexadecimal(uppercase letters).%p Displays a pointer.The Minimum Field Width Specifier Program 1.16#include int main(void)double item;item=10.12304;printf(%fn,item);printf(%10fn,item);printf(%12fn,item);return 0;10.123040 10.123040 10.123040 The Precision Specifier#include int main(void)printf(%.4fn,123.1234567);printf(%8dn,1000);printf(%.15sn,This is a simple test.);return 0;123.1235 1000 This is a simpl Justifying Output#include int main(void)printf(.n);printf(right-justified:%8dn,100);printf(left-justified:%-8dn,100);return 0;.right-justified:100 left-justified:100 Programming In CProgramming In C#include stdio.h void main()int a=2016,b=19,c=478;printf(Grade Age Score n);printf(%d%d%dn,a,b,c);printf(%d%d%dnn,a,b,c);printf(Grade Age Score n);printf(%-8d%-8d%-8dn,a,b,c);Program output Grade Age Score 201619478 2016 19 478 Grade Age Score 2016 19 478 Programming In CProgramming In C#include stdio.h void main()int a=2016,b=-19,c=478;long d=-1;short e=99000;printf(Grade Diff Scoren);printf(“%+-6d%+-5d%+-5dn”,a,b,c);printf(“%06d%5d%05dn”,a,b,c);printf(“d:%lu,%ld,%#lXn”,d,d,d);printf(“e:%hu,%hd,%#hxn”,e,e,e);Program output Grade Diff Score+2016 -19 +478 002016 -19 00478 d:4294967295,-1,0XFFFFFFFF e:33464,-32072,0 x82b8 Programming In CProgramming In C#include stdio.h void main()char ch=Y;printf(%-3c,%5sn,ch,JavaScript);printf(&ch=%pn,&ch);printf(Pass=%.1f%n,13.0/27*100);Program output Y ,JavaScript&ch=0018FF44 Pass=48.1%putchar()The putchar()function outputs one character given in parentheses on the screen.putchar(chputchar(ch）putchar(putchar(n);n);putchar(65);putchar(65);putchar(putchar(7);7);puts()The puts()function is used to display a string given in parentheses.puts(stringputs(string）puts(ID:P1588puts(ID:P1588 nName:Li PingnName:Li Ping nAge:23nAge:23 n);n);outputoutput：ID:P1588ID:P1588 Name:Li PingName:Li Ping Age:23Age:23 Programming In CProgramming In C