$B1i=,$N2rEz(B

• $BBh0l2s(B
• $BBhFs2s(B
• $BBh;02s(B
• $BBh;M2s(B
• $BBh8^2s(B
• $BBhO;2s(B
• $BBh<72s(B
• $BBhH,2s(B
• $BBh6e2s(B
• $BBh==2s(B
• $BBh==0l2s(B
• $BBh==Fs2s(B

$BBh0l2s(B

$B1i=,(B 1-1

Hello World $B$HI=<($5$l$k(B

$B1i=,(B 1-2

1. 
   #include <stdio.h>
   #define N 5
   main(){
     int i,j;
     for(i=0;i<N;i++){
       for(j=0;j<N-i;j++){
         printf("$B!{(B");
       }
       printf("\n");
     }
   }
   

2. 
   #include <stdio.h>
   #define N 4
   main(){
     int i,j;
     for(i=0;i<N;i++){
       for(j=0;j<N-i-1;j++){
         printf("$B!!(B");
       }
       for(j=0;j<2*i+1;j++){
         printf("$B!{(B");
       }
       printf("\n");
     }
   }
   

3. 
   #include <stdio.h>
   #define N 3
   main(){
     int i,j;
     for(j=0;j<N+2;j++){
       printf("$B!{(B");
     }
     printf("\n");
     for(i=0;i<N;i++){
       printf("$B!{(B");
       for(j=0;j<N;j++){
         printf("$B!!(B");
       }
       printf("$B!{(B\n");
     }
     for(j=0;j<N+2;j++){
       printf("$B!{(B");
     }
   }
   

$BBhFs2s(B

$B1i=,(B 2-1

1. 
   #include <stdio.h>
   main(){
     int a[]={5, 2, 6, 3, 1, -1};
     int i,k;
     k=0;
     for(i=0;a[i]!=-1;i++){
       k++;
     }
     printf("%d\n",k);
   }
   

2. 
   #include <stdio.h>
   main(){
     int a[]={5, 2, 6, 3, 1, -1};
     int i,goukei;
     goukei=0;
     for(i=0;a[i]!=-1;i++){
       goukei+=a[i];
     }
     printf("%d\n",goukei);
   }
   

3. 
   #include <stdio.h>
   main(){
     int a[]={5, 2, 6, 3, 1, -1};
     int i,k,goukei;
     k=0;
     goukei=0;
     for(i=0;a[i]!=-1;i++){
       k++;
       goukei+=a[i];
     }
     printf("%f\n",(float)goukei/k);
   }
   

$BBh;02s(B

$B1i=,(B 3-1

1. 
   #include <stdio.h>
   main(){
     char x[]="abc";
     int i,k;
     k=0;
     for(i=0;x[i]!='\0';i++){
       k++;
     }
     printf("%d\n",k);
   }
   

2. 
   #include <stdio.h>
   main(){
     char x[]="This is a pin.";
     int i,k;
     k=0;
     for(i=0;x[i]!='\0';i++){
       if(a[i]=='i'){
         k++;
       }
     }
     printf("%d\n",k);
   }
   

3. 
   #include <stdio.h>
   main(){
     char x[]="This is a pin.";
     int i;
     char c;
     for(i=0;x[i]!='\0';i++){
       c=x[i];
       if((c>='a')&&(c<='z')){
         c=c-'a'+'A';
       }
       printf("%c",c);
     }
   }
   

4. 
   #include <stdio.h>
   main(){
     char x[]="abc";
     char y[]="def";
     char z[50];
     int i,j;
     for(i=0;x[i]!='\0';i++){
       z[i]=x[i];
     }
     for(j=0;y[j]!='\0';j++){
       z[i]=y[j];
       i++;
     }
     z[i]='\0';
     printf("$BJ8;zNs(B %s $B$H(B %s $B$r$D$J$2$k$H(B %s $B$K$J$k(B\n",x,y,z);
   }
   

$BBh;M2s(B

1. 1. i=2, j=1
   2. i=1. j=0
   3. i=0

2. #include <stdio.h>
   main(){
     FILE *fh;
     char filename[]="4-2.c";
     char c;
     int n=0;
     if((fh=fopen(filename,"r"))!=NULL){
       while((c=getc(fh))!=EOF){
         n++;
       }
       printf("$B9g7W(B %d $BJ8;z(B\n",n);
       fclose(fh);
     }else{
       fprintf(stderr,"$B%U%!%$%k(B %s $B$r3+$1$^$;$s$G$7$?(B\n",filename);
     }
   }
   

3. #include <stdio.h>
   main(){
     FILE *fh;
     char filename[]="4-3.c";
     char c;
     char x='a';
     int n=0;
     if((fh=fopen(filename,"r"))!=NULL){
       while((c=getc(fh))!=EOF){
         if(c==x){
           n++;
         }
       }
       printf("%c $B$O9g7W(B %d $BJ8;z(B\n",x,n);
       fclose(fh);
     }else{
       fprintf(stderr,"$B%U%!%$%k(B %s $B$r3+$1$^$;$s$G$7$?(B\n",filename);
     }
   }
   

4. #include <stdio.h>
   main(){
     FILE *fh;
     char filename[]="4-4.c";
     char c;
     int n=0;
     if((fh=fopen(filename,"r"))!=NULL){
       while((c=getc(fh))!=EOF){
         if(c=='\n'){
           n++;
         }
       }
       printf("$B9g7W(B %d $B9T(B\n",n);
       fclose(fh);
     }else{
       fprintf(stderr,"$B%U%!%$%k(B %s $B$r3+$1$^$;$s$G$7$?(B\n",filename);
     }
   }
   

5. #include <stdio.h>
   main(){
     FILE *fh;
     char filename[]="4-5.c";
     char c;
     int n=0;
     if((fh=fopen(filename,"r"))!=NULL){
       while((c=getc(fh))!=EOF){
         n++;    
         if(c=='\n'){
           printf("%d $BJ8;z(B\n",n);
           n=0;
         }
       }
       if(n!=0){
         printf("%d $BJ8;z(B\n",n);
       }
       fclose(fh);
     }else{
       fprintf(stderr,"$B%U%!%$%k(B %s $B$r3+$1$^$;$s$G$7$?(B\n",filename);
     }
   }
   

6. #include <stdio.h>
   main(){
     FILE *fh;
     char filename[]="4-6.c";
   
     char c;
     int n=0;
     if((fh=fopen(filename,"r"))!=NULL){
       while((c=getc(fh))!=EOF){
         if(c=='\n'){
           printf("\n");
           n=0;
         }else{
           if(n>=10){
             printf("\n");
             n=0;
           }
           printf("%c",c);
           n++;
         }      
       }      
       fclose(fh);
     }else{
       fprintf(stderr,"$B%U%!%$%k(B %s $B$r3+$1$^$;$s$G$7$?(B\n",filename);
     }
   }
   

7. #include <stdio.h>
   #define N 3
   main(){
     FILE* fh;
     int i,j;
     if((fh=fopen("zukai.txt","w"))==NULL){
       fprintf(stderr,"$B%U%!%$%k$r3+$1$^$;$s$G$7$?(B\n");
       exit(1);
     }
     for(i=0;i<N;i++){
       for(j=0;j<N-i-1;j++){
         fprintf(fh,"  ");
       }
       fprintf(fh,"$B!{(B");
       if(i>0){
         for(j=0;j<2*i-1;j++){
   	fprintf(fh,"  ");
         }
         fprintf(fh,"$B!{(B");
       }
       fprintf(fh,"\n");
     }
     for(i=N-2;i>=0;i--){
       for(j=0;j<N-i-1;j++){
         fprintf(fh,"  ");
       }
       fprintf(fh,"$B!{(B");
       if(i>0){
         for(j=0;j<2*i-1;j++){
   	fprintf(fh,"  ");
         }
         fprintf(fh,"$B!{(B");
       }
       fprintf(fh,"\n");
     }
     fclose(fh);
   }
   

$BBh8^2s(B

$B1i=,(B 5-5

#include <stdio.h>
main(){
  char x[]="abcdef";
  char y[50];
  char *p,*q;
  p=x;
  q=y;
  while((*q++=*p++)!='\0');
  printf("%s $B$r%3%T!<$7$?7k2L(B %s $B$H$J$k(B\n",x,y);
}

$B1i=,(B 5-6

#include <stdio.h>
void copy(char *a, char *b){
  while((*b++=*a++)!='\0');
}
main(){
  char x[]="abcdef";
  char y[50];
  copy(x,y);
  printf("%s $B$r%3%T!<$7$?7k2L(B %s $B$H$J$k(B\n",x,y);
}

$BBhO;2s(B

$B1i=,(B 6-1

----distance.c----

#include "point.h"
#include <math.h>
double distance(POINT p){
   return sqrt(p.x*p.x+p.y*p.y);
}

$B1i=,(B 6-2

----half.c----

#include "point.h"
void half(POINT *p){
  p->x /= 2;
  p->y /= 2;
}

$BBh<72s(B

$B1i=,(B 7-1

5!=120, 6!=720

$B1i=,(B 7-2

1. 
   #include <stdio.h>
   int fibo(int n){
     if(n==0){ return 1; }
     if(n==1){ return 1; }
     return fibo(n-1)+fibo(n-2);
   }
   main(){
     printf("%d\n",fibo(20));
   }
   

   10946

2. 
   #include <stdio.h>
   #define N 100
   int a[N];
   int fibo(int n){
     if(a[n]>0){ return a[n];}
     if(n==0){ return 1; }
     if(n==1){ return 1; }
     a[n]=fibo(n-1)+fibo(n-2);
     return a[n];
   }
   main(){
     int i;
     for(i=0;i<N;i++){a[i]=0;}
     printf("%d\n",fibo(45));
   }
   

   a₄₀=165580141

   $BC"$7!"1i=,<<$N4D6-$@$H4JC1$K5a$^$C$F$7$^$C$?$?$a!"(B a₄₅$B$NCM(B 1836311903 $B$b5a$a$?!#(B

$B1i=,(B 7-3

#include <stdio.h>
int combi(int n, int m){
  if(m==0){ return 1; }
  if(m==n){ return 1; }
  return combi(n-1,m-1)+combi(n-1,m);
}
main(){
  printf("%d, %d\n",combi(5,2),combi(20,2));
}

10, 190 $B$,I=<($5$l$k(B

$B1i=,(B 7-4

hanoi(3,'a','b','c')

move 1 from a to b
move 2 from a to c
move 1 from b to c
move 3 from a to b
move 1 from c to a
move 2 from c to b
move 1 from a to b

hanoi(4,'a','b','c')

move 1 from a to c
move 2 from a to b
move 1 from c to b
move 3 from a to c
move 1 from b to a
move 2 from b to c
move 1 from a to c
move 4 from a to b
move 1 from c to b
move 2 from c to a
move 1 from b to a
move 3 from c to b
move 1 from a to c
move 2 from a to b
move 1 from c to b

$BBhH,2s(B

$B1i=,(B 8-1

14$B

$B1i=,(B 8-2

$B1i=,(B 8-3

#include 
#define MAX 10
main(){
  int i,j,degree,kiten;
  int a[MAX][MAX];
  printf("$BD:E@?t$rF~$l$F2<$5$$!#(B\n");
  scanf("%d",&n);
  kiten=0;
  for(i=0;i<n;i++){
    degree=0;    
    for(j=0;j<n;j++){
      scanf("%d",&a[i][j];);
      degree+=a[i][j];
    }
    kiten+=degree%2
  }
  if((kiten==0)||(kiten==2)){
    printf("$B0lI.=q$-$G$-$^$9!#(B\n");
  }else{
    printf("$B0lI.=q$-$G$-$^$;$s!#(B\n");
  }
}

$BBh6e2s(B

$B1i=,(B 9-1

#include <stdio.h>
#include <string.h>
#include <stdlib.h>
#define SIZE 80
char buffer[SIZE+1];
typedef struct lst {
  char *item;
  struct lst *next;
} LIST;
LIST* newnode(){
   LIST *p;
   p=(LIST *)malloc(sizeof(LIST));
   p->next=NULL;
   return p;
}
void add(LIST *p,char *c){
  if(p->next == NULL){
    p->item=c;
    p->next=newnode();
  }else{
    add(p->next,c);
  }
}  
void reverseshow(LIST *p){
  if(p->next != NULL){
    reverseshow(p->next);
    printf("%s\n",p->item);
  }
}
main(){
  char c;
  int i=0;
  char filename[]="input.txt";
  FILE *fh;
  LIST *l;
  l=newnode();
  if((fh=fopen(filename,"r"))!=NULL){
    while((c=getc(fh))!=EOF){
      if(c!='\n'){
	if(i<SIZE){
	  buffer[i++]=c;
	}
      }else{
	buffer[i]='\0';
	add(l,strdup(buffer));
	i=0;
      }
    }
    reverseshow(l);
    fclose(fh);
  }else{
    fprintf(stderr,"$B%U%!%$%k(B %s $B$,$"$j$^$;$s!#(B\n",filename);
  }
}

$B1i=,(B 9-2

$B:[email protected](B

$BBh==2s(B

$B1i=,(B 10-1

$B

def
ghi
abc

$B1i=,(B 10-2

$BNc(B 2 $B$H=EJ#(B

$B1i=,(B 10-3

$B:[email protected](B

$BBh==0l2s(B

$B1i=,(B 11-1

$B:[email protected](B

$B1i=,(B 11-2

show $B4X?t$r0J2<$N$h$&$K=q$-D>$9!#(B

void show(TREE *t){
  if(t!=NULL){
    show(t->right);
    printf("%s: %d\n",t->id,t->key);
    show(t->left);
  }
}

$B1i=,(B 11-3

$BN,(B

$B1i=,(B 11-4

$BBh==Fs2s(B

$B1i=,(B 12-1

#include <stdio.h>
int a[11]={4,6,3,1,9,7,5,0,2,6,8};
void printarray(){
  int i;
  for(i=0;i<11;i++){
    printf("%d ",a[i]);
  }
  printf("\n");
}
void partition(int s, int t){
  if(s<t){
    int val = a[s];
    int i=s+1,j=t;
    int tmp;
    while(i<=j){
      while((i<=t)&&(val>=a[i])){i++;}
      while((j>=s+1)&&(val<a[j])){j--;}
      if(i<j){
	tmp=a[i];
	a[i]=a[j];
	a[j]=tmp;
      }
    }
    if(i-1>=s+1){
      tmp=a[s];
      a[s]=a[i-1];
      a[i-1]=tmp;
    }
    partition(s,i-2);
    partition(j+1,t);
  }
}
main(){
  printarray();
  partition(0,10);
  printarray();
}