实验4

实验任务1：

include<stdio.h>

define N 4

define M 2

void test1(){
int x[N]={1, 9, 8, 4};
int i;
printf("sizeof(x)=%d\n",sizeof(x));
for(i=0;i<N;++i)
printf("%p:%d\n",&x[i],x[i]);
printf("x=%p\n",x);
}
void test2(){
int x[M][N]={{1, 9, 8, 4},{2, 0, 4, 9}};
int i, j;
printf("sizeof(x)=%d\n",sizeof(x));
for(i=0;i<N;++i)
for(j=0;j<N;++j)
printf("%p:%d\n",&x[i][j],x[i][j]);
printf("\n");
printf("x=%p\n",x);
printf("x[0]=%p\n",x[0]);
printf("x[1]=%p\n",x[1]);
printf("\n");
}
int main(){
printf("测试1：int型一维数组\n");
test1();
printf("\n测试2：int型二维数组\n");
test2();
return 0;
}

问题1：是，一样

问题2：是，不一样，差值是一行元素所占字节数，意义在于反映二维数组在内存中按行存储时相邻两行之间的地址偏移量。
实验任务2：

include<stdio.h>

define N 100

void input(int x[],int n);
double compute(int x[],int n);
int main(){
int x[N];
int n, i;
double ans;
while(printf("Enter n:"),scanf("%d",&n)!=EOF){
input(x,n);
ans = compute(x, n);
printf("ans = %.2f\n\n",ans);
}
return 0;
}
void input(int x[N],int n){
int i;
for(i=0;i<n;++i)
scanf("%d",&x[i]);
}
double compute(int x[],int n){
int i, high, low;
double ans;
high=low=x[0];
ans=0;

for(i=0;i<n;++i){
    ans+=x[i];
    if(x[i]>high)
        high=x[i];
    else if(x[i]<low)
        low=x[i];
}
ans = (ans-high-low)/(n-2);
return ans;

}

问题：input是从键盘录入n个数，compute是求数组删去最大值和最小值后的平均数

实验任务3：

include <stdio.h>

define N 100

void output(int x[][N], int n);
void init(int x[][N], int n, int value);

int main(){
int x[N][N];
int n, value;

while(printf("Enter n and value: "), scanf("%d%d", &n, &value) != EOF) {
    init(x, n, value);  
    output(x, n);      
    printf("\n");
}

return 0;

}
void output(int x[][N], int n){
int i, j;

for(i = 0; i < n; ++i) {
    for(j = 0; j < n; ++j)
        printf("%d ", x[i][j]);
    printf("\n");
}

}
void init(int x[][N], int n, int value){
int i, j;

for(i = 0; i < n; ++i)
    for(j = 0; j < n; ++j)
        x[i][j] = value;

}

问题1：第二维不可省略

问题2：output是定义一个n阶方阵，init是将value输入方阵中

实验任务4：

include<stdio.h>

define N 100

void input(int x[],int n);
float median(int x[],int n);

int main(){
int x[N];
int n;
double ans;
while(printf("Enter n:"),scanf("%d",&n)!=EOF){
input(x, n);
ans = median(x, n);
printf("ans = %g\n\n", ans);
}
return 0;
}

void input(int x[], int n){
int i;
for (int i = 0;i < n; i++){
scanf("%d",&x[i]);
}
}
float median(int x[],int n){
int i,j;
for(i=0;i<n-1;++i){
for(j=0;j<n-i-1;j++){
if(x[j]>x[j+1]){
int temp = x[j];
x[j]=x[j+1];
x[j+1]=temp;
}
}
}
if(n%2!=0){
return x[n/2];
}
else{
return (x[n/2-1]+x[n/2])/2.0;
}
}

实验任务5：

include <stdio.h>

define N 100

void input(int x[][N], int n);
void output(int x[][N],int n);
void rotate_to_right(int x[][N],int n);

int main(){
int x[N][N];
int n;

printf("Enter n: ");
scanf("%d",&n);
input(x, n);
printf("原始矩阵：\n");
output(x, n);

rotate_to_right(x, n);
printf("变换后矩阵：\n");
output(x, n);

return 0;

}

void input(int x[][N], int n){
int i,j;

for(i=0;i<n;++i){
    for (j = 0;j<n;++j)
        scanf("%d",&x[i][j]);
}

}

void output(int x[][N], int n){
int i,j;

for(i = 0;i<n;++i){
    for(j=0;j<n;++j)
        printf("%4d",x[i][j]);
    
    printf("\n");
    
}

}

void rotate_to_right(int x[][N],int n){
int temp[N];
int i,j ;
for (j=0;j<n;j++){
temp[j]=x[j][n-1];
for(i=n-1;i>0;i--){
x[j][i]=x[j][i-1];
}
x[j][0]=temp[j];
}
}

实验任务6：

include<stdio.h>

define N 100

void dec_to_n(int x,int n);

int main(){
int x;
while(printf("输入十进制整数："),scanf("%d",&x) !=EOF){
dec_to_n(x, 2);
dec_to_n(x, 8);
dec_to_n(x, 16);

    printf("\n");
}
return 0;

}

void dec_to_n(int x, int n) {
char result[100];
int i = 0;
int j;
while (x > 0) {
int remainder = x % n;
if (n == 16 && remainder >= 10) {
if (remainder == 10) {
result[i++] = 'A';
} else if (remainder == 11) {
result[i++] = 'B';
} else if (remainder == 12) {
result[i++] = 'C';
} else if (remainder == 13) {
result[i++] = 'D';
} else if (remainder == 14) {
result[i++] = 'E';
} else if (remainder == 15) {
result[i++] = 'F';
}
} else {
result[i++] = remainder + '0';
}
x /= n;
}
result[i] = '\0';
for (j = i - 1; j >= 0; j--) {
printf("%c", result[j]);
}
printf("\n");
}

实验任务7：

include<stdio.h>

define N 100

void input(int x[][N], int n);
void output(int x[][N], int n);
int is_magic(int x[][N], int n);

int main(){
int x[N][N];
int n;

while(printf("输入n: "),scanf("%d",&n) !=EOF){
    printf("输入方阵：\n");
    input(x, n);
    
    printf("输出方阵：\n");
    output(x, n);
    
    if(is_magic(x, n))
        printf("是魔方矩阵\n\n");
    else
        printf("不是魔方矩阵\n\n");
}
return 0;

}

void input(int x[][N],int n){
int i,j;

for(i = 0;i<n;++i){
    for(j = 0;j < n;++j)
        scanf("%d",&x[i][j]);
        
}

}

void output(int x[][N],int n){
int i,j;
for(i=0;i<n;++i){
for(j=0;j<n;++j)
printf("%4d",x[i][j]);
printf("\n");
}
}
int is_magic(int x[][N],int n){
int sum = 0;
int m,i,j;
for (i=0;i<n;i++){
sum+=x[0][i];
}
for (i=0;i<n;i++){
m=0;
for (j=0;j<n;j++){
m+=x[i][j];
}
if(m!=sum)
return 0;
}
m = 0;
for(i=0;i<n;i++){
m+=x[i][i];
}
if(m!=sum){
return 0;
}
m=0;
for (i=0;i<n;i++){
m+=x[i][n-1-i];
}
if(m!=sum){
return 0;
}
return 1;
}

实验任务8：

include <stdio.h>

int checkNumber(int num);
int main() {
int i;
for (i = 1; i < 10000; i++) {
if (checkNumber(i)) {
printf("%d\n", i);
break;
}
}
return 0;
}
int checkNumber(int num) {
int digitUsed[10] = {0};
int square = num * num;
int cube = num * num * num;

while (square > 0) {
    digitUsed[square % 10] = 1;
    square /= 10;
}

while (cube > 0) {
    digitUsed[cube % 10] = 1;
    cube /= 10;
}
int i;
for ( i = 0; i < 10; i++) {
    if (digitUsed[i] == 0) {
        return 0;
    }
}
return 1;

}