第四章学习贴：

//ex040201.c
#include <stdio.h>
void main(void)
{
int i, a[10];
for(i=0; i<10; i++)
a[i]=i;
for(i=9;i>=0;i--)
printf("%d",a[i]);
}

//ex040202.c
#include <stdio.h>
void main( void )
{
int a[20]={12,32,45,6,78,88,21,34,43,46};
int i=0, k=0;
while(a[i])
{
if(a[i]%2==0 || a[i]%5==0)
k++;
i++;
}
printf("%d,%d", k,i);
}

//ex040203.c
#include <stdio.h>
void main( void )
{
int aa[100],n,i,k;
for(n=0, i=1;i<=100;i++)
if(i%7==0&&i%11||i%7&&i%11==0)
aa[n++]=i;
for(k=0;k<n;k++)
if((k+1)%10==0 )
printf("\n");
else
printf("%5d",aa[k]);
}

//ex040204.c
#include <stdio.h>
void main(void)
{
inta[3][3]={1,2,3,4,5,6,7,8,9},i;
for(i=0;i<3; i++)
printf("%d,",a[i][2-i]);
}

//ex040205.c
#include <stdio.h>
void main( void )
{
char str[10]="abcdef", tmp;
int i, j;
for(i=1; i<3; ++i)
{
tmp=str[5];
for(j=4; j>=0; --j)
str[j+1]=str[j];
str[0]=tmp;
}
printf("%s,",str);
}

//ex040206.c
#include <stdio.h>
void main( void )
{
char s[]="kjihgfedcba";
int p=9;
while(s[p]!= 'i')
printf("%c", s[p--]);
}

//ex040207.c
#include <stdio.h>
#include <string.h>
void main( void )
{
char str[30];
strcpy(&str[0], "CHINA");
strcpy(&str[1],"DEFINE");
strcpy(&str[2],"ARM");
printf("%s\n",str);
}

//ex040208.c
#include <stdio.h>
void main( void )
{
char s[80]= "wereteye", c='e';
int i, j;
for(i=j=0; s[i]!= '\0'; i++)
if(s[i]!=c)
s[j++]=s[i];
s[j]='\0';
puts(s);
}

说明：贴吧滤除了程序的缩进，请同学们自行补充。

//ex040301.c
#include <stdio.h>
#define SIZE 10
void main(void)
{
float Num[SIZE], tmp;
short i, j;
printf("Input 10 n ormal numbers: ");
/******ERROR******/
scanf("%f", &Num);
for(i=0; i<SIZE-1; i++)
{
for( j=0; j<SIZE-i-1; j++)
if(Num[j]>Num[j+1])
tmp=Num[j], Num[j]=Num[j+1], Num[j+1]=tmp;
}
printf("Sorted numbers:");
printf("%5.1f\n ",Num);
}

//ex040302.c
#include <stdio.h>
void main( void )
{
/*******ERROR*******/
short i, s, n, a[]={27, 56,123, 128, 154, 168, 178, 205, 362, 618};
printf("input a number:\n");
scanf("%d", &n);
for(i=0; i<10; i++)
/***ERROR***/
if(n>a[i])
{
for(s=9; s>=i; s--)
a[s+1]=a[s];
break;
}
a[i]=n;
for(i=0; i<=10; i++)
printf("%d ", a[i]);
printf("\n");
}

//ex040303.c
#include<stdio.h>
/*******ERROR*******/
void main(void)
{
char StrName[5][10], Strtmp[10];
short i, j, tmp;
printf("input country's name:\n");
for(i=0;i<5;i++)
gets(StrName[i]);
for(i=0;i<5;i++)
{
for(tmp=i, j=i+1; j<5; j++)
/************ERROR************/
if( StrName[j] < StrName[tmp] )
tmp=j;
if(tmp!=i)
{
/*********ERROR*********/
Strtmp = StrName[tmp];
StrName[tmp] = StrName[i];
StrName[i] = Strtmp;
}
puts( StrName[i] );
}
}
}

//ex040305.c
#include <stdio.h>
#define 10
void main(void )
{
int x[SIZE], i, pos;
printf("Enter %d integers:\n", SIZE);
for(i=0; i<SIZE; i++)
/******ERROR******/
printf("%d:",i);
scanf("%d",&x[i]);
pos=0;
for(i=0; i<SIZE; i++)
/******ERROR******/
if(pos>x[i])
pos=i;
printf("Minimum value is %d, No%d.\n", x[pos], pos+1);
}

#include <stdio.h>
#define N 1000
void main(void)
{
int r[N]={1};
int i, j;
int k=0, l=0;
for(i=1;i<=40;i++)
{
for(j=0;j<=l;j++)
{
r[j]=r[j]*i+k;
k=r[j]/10;
r[j]=r[j]%10;
}
while(k) //进位
{
l++;
r[j++]=k%10;
k=k/10;
}
j=l;
printf("%d!=%d",i,r[j--]);
for(;j>=0;j--)
{
printf("%d",r[j]);
}
printf("\n");
}
}