实验1

task1

#include<stdio.h>
int main()
{
printf(" O\n");
printf("<H>\n");
printf("I I\n");
printf(" \n");
printf(" O\n");
printf("<H>\n");
printf("I I\n");
printf(" \n");
printf(" O O\n");
printf("<H> <H>\n");
printf("I I I I\n");

return 0;
}

 task2

#include<stdio.h>
int main()
{

float x, y;
float r1, r2, r3, r4;

x = 1;
y = 2;

r1 = x + y;
r2 = x - y;
r3 = x * y;
r4 = x / y;

printf("r1=%f\n", r1);
printf("r2=%f\n", r2);
printf("r3=%f\n", r3);
printf("r4=%f\n", r4);

return 0;
}

 r4不同原因：math1.cpp中各数据都是整形，math2.cpp中各数据都是浮点型

task3

#include<stdio.h>
int main(){
    int n, r1, r2, r3, r4;

    n = 100;

    r1 = n * (n + 1) / 2;
    r2 = (n + 1) * n / 2;
    r3 = n / 2 * (n + 1);
    r4 = (n + 1) / 2 * n;

    printf("n=%d\n", n);
    printf("r1=%d\n", r1);
    printf("r2=%d\n", r2);
    printf("r3=%d\n", r3);
    printf("r4=%d\n", r4);

    return 0;
}

#include<stdio.h>
int main() {
    int n, r1, r2, r3, r4;

    n = 101;

    r1 = n * (n + 1) / 2;
    r2 = (n + 1) * n / 2;
    r3 = n / 2 * (n + 1);
    r4 = (n + 1) / 2 * n;

    printf("n=%d\n", n);
    printf("r1=%d\n", r1);
    printf("r2=%d\n", r2);
    printf("r3=%d\n", r3);
    printf("r4=%d\n", r4);

    return 0;
}

 

数据类型都为整形

当n为偶数时，r3中n/2为整数结果与r1r2一致，r4中(n+1)/2向下取整导致结果不一样

当n为奇数时，r3中n/2不为整数结果与r1r2不一致，r4中(n+1)/2为整数结果与r1r2一样

task4

#define _CRT_SECURE_NO_WARRNINGS
#include<stdio.h>
int main()
{
    double x, y;
    char c1, c2, c3;
    int a1, a2, a3;

    scanf("%c %c %c", &c1, &c2, &c3);
    printf("%c,%c,%c\n" ,c1, c2, c3);
    scanf("%d%d%d", &a1, &a2, &a3);
    printf("%d,%d,%d\n", a1, a2, a3);
    scanf("%lf%lf", &x, &y);
    printf("%lf,%lf", x, y);
    
    return 0;
}

 task5

#define _CRT_SECURE_NO_WARRNINGS
#include<stdio.h>
int main()
{
    int a1, a2;
    char c1, c2;

    scanf("%d%c%d%c", &a1, &c1, &a2, &c2);
    printf("a1=%d,a2=%d\n", a1, a2);
    printf("c1=%c,c2=%c\n", c1, c2);

    return 0;
}

 task6

#include<stdio.h>
int main()
{
    int answer;
    char words[5000];

    printf("网课学习让一些人欢喜一些人忧。\n");
    printf("1.作为一个宅，社恐，觉得这样很好，有网络，自主学习，很ok。\n");
    printf("2.不喜，不喜，很不喜，眼睛快瞎了，脑壳有点卡...\n");
    printf("3.中间派，不知道，说不清。\n");
    printf("4.其他...\n");
    printf("你的选择：");
    scanf_s("%d", &answer);
    if (answer == 4) {
        printf("请补充说明你的想法：\n");
        getchar();
        gets_s(words);
    }
    printf("\n");
    printf("当遇到问题，你会选择：\n");
    printf("1.遇到问题，就解决问题，不懂得，搜索式学习，逐个攻破\n");
    printf("2.遇到问题，不高兴，然后......就没有了\n");
    printf("3.其他...\n");
    printf("你的选择：");
    scanf_s("%d", &answer);

    if (answer == 1)
        printf(":)\n");
    else if (answer == 2)
        printf("这样不能解决问题啊...我们选择1好不好:)\n");
    else if (answer == 3) {
        printf("请补充说明你的想法：\n");
        getchar();
        gets_s(words);
    }

    return 0;
}