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 < M; ++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;
}

 

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[], 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;
}

 

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;
}

 

实验任务4

#include <stdio.h>
#define N 100

 double median(int x[N], int n);
 void input(int x[N], 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;
 }


 double median(int x[N], int n){
     int t, i, j, temp;

     for(i = 0; i < n - 1; i++){
         for(j = 0; j < n - 1 -i; j++){
             if(x[j] > x[j + 1]){
                 temp = x[j];
                 x[j] = x[j + 1];
                 x[j + 1] = temp;
             }
         }
     }

     t = n/2;

     if(n % 2 != 0)
         return x[t];


     if(n % 2 == 0)
         return (x[t - 1] + x[t]) / 2.0;
 }

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

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

 

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("输入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, i, j;
    for(i = 0; i < n; ++i){
        temp = x[i][n - 1];

        for(j = n - 1; j > 0; --j){
            x[i][j] = x[i][j - 1];
        }

        x[i][0] = temp;
    }

}

 

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 ans[100];
    char map[] = "0123456789ABCDEF";
    int r, i, cnt;
    cnt = 0;

    do{
        r = x  % n;
        ans[cnt++] = map[r];
        x = x/n;
    }while(x != 0);

    for(i = cnt - 1; i >= 0; --i)
        printf("%c", ans[i]);
    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 sum1, sum2, sum3, sum4, i, j, t;
    sum2 = 0;
    sum3 = 0;
    sum4 = 0;
    t = n*(n*n + 1) / 2;

    for(i = 0; i < n; ++i){
        sum1 = 0;
        for(i = 0; i < n; ++i){
            sum1 += x[i][j];

        }
        if(sum1 != t)
            return 0;
    }

    for(i = 0; i < n; ++i){
        sum2 = 0;
        for(i = 0; i < n; ++i){
            sum2 += x[i][j];

        }
        if(sum2 != t)
            return 0;
    }

    for(i = 0; i < n; ++i){
        sum3 += x[i][i];
        sum4 += x[i][n - 1 - i];
    }
    if(sum3 != t || sum4 != t)
        return 0;

    return 1;
}