一

//命令行加法计算
//需要在命令行中运行
#include <iostream>

int main(int argc,char** argv)
{
    int sum = 0;
    int i = 1;
    while (argv[i] != NULL) {
        sum += atoi(argv[i]);
        i++;
    }
    printf("Total=%d", sum);
}

二

#include <iostream>

struct flight {
    int time;
    int arrive;
};
void TimeChangePrint(int time);
int main()
{
    struct flight timetable[8] = {
        {480,616},
        {583,712},
        {679,811},
        {767,900},
        {840,968},
        {945,1075},
        {1140,1280},
        {1305,1438}
    };
    int Nowtime = 0;
    printf("Enter a 24-hour time:");
    int hour, min;
    scanf_s("%d:%d", &hour, &min);
    Nowtime = (hour - 1) * 60 + min;
    for (int i = 0; i < 8; i++) {
        if ((timetable[i].time) >= Nowtime) {
            printf("Clost departure time is ");
            TimeChangePrint(timetable[i].time);
            printf(", arriving at ");
            TimeChangePrint(timetable[i].arrive);
            break;
        }
    }
}
void TimeChangePrint(int time) {
    if (time < 720) {
        printf("%d:%02d a.m.", time / 60, time % 60);
    }
    else if (time < 780) {
        printf("12:%02d p.m.", time % 60);
    } else{
        printf("%d:%02d p.m.", (time - 720) / 60, time % 60);
    }
}

三

#include<stdio.h>
#include<stdlib.h>
#include<string.h>
int main()
{
    char* word[100];
    char in[20];
    int i = 0;
    while (1) {
        int a = 0;
        printf("Enter word:");
        while ((in[a] = getchar() )!= '\n')a++;
        if (a == 0)break;
        in[a] = 0;
        word[i++] = (char*)malloc(sizeof(char) * a);
        for (int n = 0; n < a; n++)word[i - 1][n] = in[n];
    }
    for (int n = 0; n < i - 1; n++) {
        for (int c = 0; c < i - 1 - n; c++) {
            if (strcmp(word[c], word[c + 1]) > 0) {
                char* temp = word[c];
                word[c] = word[c + 1];
                word[c + 1] = temp;
            }
        }
    }
    printf("In sorted order:");
    for(int n=0;n<i;n++) {
        printf("%s ", word[n]);
    }
}