CI/OI/O
#include <stdio.h>
,”
%[]
d,i
x,X
o
u
c
s
e,E
f
g
%%
ef
int a=567;printf (,%d”,a);
int a=255;printf(“%x”,a);
int a=65;printf(“%o”,a);
int a=567;printf(“%u”,a);
char a=65;printf(“%c”,a);
printf(“%s”,“ABC”);
float a=567.789;printf(“%e”,a);
float a=567.789;printf(“%f”,a);
float a=567.789;printf(“%g”,a);
printf(“%%”);
567
ff
101
567
A
ABC
5.677890e+02
567.789000
567.789
%
:,
.n
,()
m
-
+
0
#
l
int a=1234;
float f=123.456;
printf(“%08d\n”,a);
printf(“%010.2f\n”,f);
printf(“%0+8d\n”,a);
printf(“0+10.2f\n”,f);
0 +
int a=123;
printf(“%o,%#o,%X,%#X\n”,a,a,a,a);
#
long a=65536;
printf(“%d,%8ld\n”,a,a);
l 00 00 00 00 00 00 00 01 00 00 00 00 00 00 00 00
//00001234
//0000123.46
//000+1234//000+123.56
//173,0173,7B,0X7B
//0,65536
/*ch3_4.c*/
#include <stdio.h>
main()
{ int c;
printf("Enter a character:");
c=getchar();
printf("%c--->hex%x\n",c,c);
}
Enter a character:A?
A--->hex41
“
scanf(“%d”,&a);
10?
a=10
scanf(“%x”,&a);
11?
a=17
l
h
m
*
scanf(“%4d%2d%2d”,&yy,&mm,&dd);
19991015?
1999?yy,10?mm,15?dd
TAB
scanf(“%d%o%x”,&a,&b,&c);
printf(“a=%d,b=%d,c=%d\n”,a,b,c);
123 123 123?
a=123,b=83,c=291
scanf(“%d:%d:%d”,&h,&m,&s);
12:30:45?
12?h,30?m,45?s
scanf(“%d,%d”,&a,&b)
3,4?
3?a,4 bscanf(“a=%d,b=%d,c=%d”,&a,&b,&c);a=12,b=24,c=36?
%c”
scanf(“%c%c%c”,&c1,&c2,&c3);
abc?
a?c1,?c2,b?c3
TAB
scanf(“%d%c%f”,&a,&b,&c);
1234a123o.26?
1234?a,?ab,123?c
int x;
char ch;
scanf(“%d”,&x);
ch=getchar();
printf(“x=%d,ch=%d\n”,x,ch);
123?
x=123,ch=10
int x;
char ch;
scanf(“%d”,&x);
scanf(“%c”,&ch);
printf(“x=%d,ch=%d\n”,x,ch);
123?
x=123,ch=10
”
int x;
char ch;
scanf(“%d”,&x);
scanf(,%c”,&ch);
scanf(“%*c%c”,&ch);
/*ch3_12.c*/
#include <math.h>
#include <stdio.h>
main()
{ float a,b,c,s,area;
scanf("%f,%f,%f",&a,&b,&c);
s=1.0/2*(a+b+c);
area=sqrt(s*(s-a)*(s-b)*(s-c));
printf("a=%7.2f,b=%7.2f,c=%7.2f,s=%7.2f\n",a,b,c,s);
printf("area=%7.2f\n",area);
}
3,4,6?
a= 3.00,b= 4.00,c= 6.00 s= 6.50
area= 5.33
/*ch3_13.c*/
#include "stdio.h"
main()
{ char c1,c2;
c1=getchar();
printf("%c,%d\n",c1,c1);
c2=c1+32;
printf("%c,%d\n",c2,c2);
}
A?
A,65
a,97
