#没有无用功 凡学必有用 自律更自由# 14-2#include
#include
void fun(char t[])
{
char c;
int i,j;
/*************found**************/
for(i=strlen(t)-1;i;i--)

for(j=0;j

/*************found**************/

if(t[j]>t[j+1])

{

c= t[j];

t[j]=t[j+1];

t[j+1]=c;

}
}
main()
{
char s[81];

printf("\nPlease enter a character string :");
gets(s);
printf("\n\nBefore sorting :\n %s",s);
fun(s);
printf("\nAfter sorting decendingly:\n %s",s);
}

#没有无用功 凡学必有用 自律更自由# 13-1 #include
#include
#include
#include
char *fun(char *s)
{ int i, j, k, n;

char *p, *t;
n=strlen(s)+1;
t=(char*)malloc(n*sizeof(char));
p=(char*)malloc(n*sizeof(char));
j=0; k=0;
for(i=0; i { if(isdigit(s[i])) {
/**********found**********/

p[j]=s[i]; j++;}

else

{ t[k]=s[i]; k++; }

}
/**********found**********/

for(i=0; i

p[j+k]=0;
/**********found**********/

return p;
}
main()
{ char s[80];
printf("Please input: "); scanf("%s",s);
printf("\nThe result is: %s\n",fun(s));
}

基于51单片机非中断延时制作的呼吸灯

#include "stc12c5a60s2.h"
#define uchar unsigned char
#define uint unsigned int

sbit led=P0^4;

void delayedms(uchar time){

uchar i,j;
for(i=time;i>0;i--)
for(j=110;j>0;j--);
}
void delayedus(uint time){

while(time--);
}
void led_Hande(void){

uint cycle=500,pwm_low=0;

/*周期与PWM载波*/

delayedms(200);

for(pwm_low=1;pwm_low
led=0;
delayedus(pwm_low);
led=1;
delayedus(cycle-pwm_low);
}
led=1;
for(pwm_low=cycle-1;pwm_low>0;pwm_low--){ /*由暗变亮*/

led=0;
delayedus(pwm_low);
led=1;
delayedus(cycle-pwm_low);
}
}
/*------------------------------
板块：PWM波调制呼吸灯
--------------------------------*/
#include "stc12c5a60s2.h"
#define uchar unsigned char
#define uint unsigned int

#pragma SAVE
#pragma REGPARMS

extern void led_Hande(void);

void main(void){

P0M0=0xff;
P0M1=0x00;

while(1){

led_Hande();
}
}

#pragma RESTORE