实验三

任务一

代码

#include <stdio.h>
#include <stdlib.h>
#include <time.h>
#include <windows.h>
#define N 80
void print_text(int line, int col, char text[]);
void print_spaces(int n);
void print_blank_lines(int n); 
int main() {
    int line, col, i;
    char text[N] = "hi, April~";
    srand(time(0));
    for(i = 1; i <= 10; ++i) {
        line = rand() % 25;
        col = rand() % 80;
        print_text(line, col, text);
        Sleep(1000); 
}
return 0;
}

void print_spaces(int n) {
    int i;
    for(i = 1; i <= n; ++i)
    printf(" ");
}

void print_blank_lines(int n) {
    int i;
    for(i = 1; i <= n; ++i)
    printf("\n");
}
void print_text(int line, int col, char text[]) {
    print_blank_lines(line-1); 
    print_spaces(col-1); 
    printf("%s", text);
} 

结果

task2.1

代码

#include <stdio.h>
long long fac(int n);
int main() {
    int i, n;
    printf("Enter n: ");
    scanf("%d", &n);


    for (i = 1; i <= n; ++i)
    printf("%d! = %lld\n", i, fac(i));
    return 0;
}
long long fac(int n) {
static long long p = 1;
p = p * n;
return p;
} 

结果

task2.2

代码

#include <stdio.h>
int func(int, int); 
int main() {
    int k = 4, m = 1, p1, p2;
    p1 = func(k, m); 
    p2 = func(k, m); 
    printf("%d, %d\n", p1, p2);
     return 0;
}
int func(int a, int b) {
    static int m = 0, i = 2;
    i += m + 1;
    m = i + a + b;
    return m;
}

结果

task3

代码

#include <stdio.h>
long long func(int n); 
int main() {
    int n;
    long long f;
    while (scanf("%d", &n) != EOF) {
        f = func(n); 
        printf("n = %d, f = %lld\n", n, f);
}
return 0;
}
long long func(int n){
    int i;
    long long m=0;
    for(i=1;i<=n;i++){
        m=(m+1)*2-1;
    }
    return m;
}

结果

task4

代码

#include <stdio.h>
int func(int n, int m);

int main() {
    int n, m;

    while(scanf("%d%d", &n, &m) != EOF)
        printf("n = %d, m = %d, ans = %d\n", n, m, func(n, m));
    
    return 0;
}

int func(int n,int m){
    int C;
    if(m==0||m==n)
       C=1;
    else
        if(m>n)
          C=0;
        else
          C=func(n-1,m)+func(n-1,m-1);
    
    return C;
}

结果

task5.1

代码

#include <stdio.h>
double mypow(int x, int y);

int main() {
    int x, y;
    double ans;
    
    while(scanf("%d%d", &x, &y) != EOF) {
        ans = mypow(x, y);    
        printf("%d的%d次方: %g\n\n", x, y, ans);
    }
    return 0;
} 

double mypow(int x,int y){
    double ans=1;
    int i;
    if(y>=0)
        for(i=0;i<y;i++)
           ans=ans*x;
    else
        for(i=0;i>y;i--)
           ans=ans/x;
    
    return ans;
}

结果

task5.2

代码

#include <stdio.h>
#include <math.h>
double mypow(int x, int y);

int main() {
    int x, y;
    double ans;
    
    while(scanf("%d%d", &x, &y) != EOF) {
        ans = mypow(x, y);    
        printf("%d的%d次方: %g\n\n", x, y, ans);
    }
    return 0;
} 

double mypow(int x,int y){
    double ans;
    if(y==0)
        ans=1;
    else
        ans=x*mypow(x,fabs(y)-1);
    if(y<0)
        ans=1/ans;    
    return ans;
}

结果

task6

代码

#include <stdio.h>
#include <stdlib.h>
void hanio(unsigned int n,char from,char temp,char to);
void moveplate(unsigned int n,char from,char to);
int i;
int main(){
    unsigned int n;
    while(scanf("%u",&n)!=EOF){
        hanio(n,'A','B','C');
        printf("一共移动了%d次。\n",i);
        i=0;
    }
    return 0;
}
void hanio(unsigned int n,char from,char temp,char to){
    if(n==1)
        moveplate(n,from,to);
    else{
        hanio(n-1,from,to,temp);
        moveplate(n,from,to);
        hanio(n-1,temp,from,to);
    }
}
void moveplate(unsigned int n,char from,char to){
    printf("%u:%c-->%c\n",n,from,to);
    i++;
}

结果

task7

代码

#include <stdio.h>
#include <math.h>
int is_prime(double n);
int sovle(int ans);
int main(){
    int n,ans;
    while(scanf("%d",&ans)!=EOF){
        n=sovle(ans);
        printf("%d=%d+%d\n",ans,ans-n,n);
    }
    return 0;
} 
int sovle(int ans){
    double n=ans-2.0;
    while(is_prime(n)==0||is_prime(ans-n)==0){
        n--;
    }
    return (int)n;
}
int is_prime(double n){
    int m;
    for(m=2;;m++){
        if(m>sqrt(n))
            return 1;
        else
            if((int)n%m==0)
                return 0;
    }
}

结果

task8

代码

#include <stdio.h>
#include <math.h>
long func(long s);
int main(){
    long s,t;
    printf("Enter a number:");
    while(scanf("%ld",&s)!=EOF){
        t=func(s);
        printf("new number is:%ld\n\n",t);
        printf("Enter a number:");
    }
    return 0;
}
long func(long s){
    int t=0;
    double i;
    while(s!=0){
        if(s%10%2==1)
            t=t+s%10*pow(10.0,i),i++;
        s=s/10;
    }
    return t;
}

结果