练习题1： 编写一个程序，计算并输出两个整数之和。
#include <stdio.h>
int main() {
int num1, num2;
printf("Enter two integers: ");
scanf("%d %d", &num1, &num2);
int sum = num1 + num2;
printf("The sum of %d and %d is %d\n", num1, num2, sum);
return 0;
}练习题2： 编写一个程序，判断用户输入的年份是否为闰年。闰年的条件是：能被4整除但不能被100整除，或者能被400整除。
#include <stdio.h>
int main() {
int year;
printf("Enter a year: ");
scanf("%d", &year);
if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) {
printf("%d is a leap year.\n", year);
} else {
printf("%d is not a leap year.\n", year);
}
return 0;
}练习题3： 编写一个程序，计算并输出给定整数数组的所有元素之和。
#include <stdio.h>
int main() {
int arr[] = {10, 20, 30, 40, 50};
int n = sizeof(arr) / sizeof(arr[0]);
int sum = 0;
for (int i = 0; i < n; i++) {
sum += arr[i];
}
printf("The sum of all elements in the array is %d\n", sum);
return 0;
}练习题4： 编写一个程序，实现字符串反转功能。
#include <stdio.h>
#include <string.h>
void reverse(char* str) {
int len = strlen(str);
for (int i = 0; i < len / 2; i++) {
char temp = str[i];
str[i] = str[len - i - 1];
str[len - i - 1] = temp;
}
}
int main() {
char str[100];
printf("Enter a string: ");
fgets(str, sizeof(str), stdin);
str[strcspn(str, "\n")] = '\0'; // Remove trailing newline
reverse(str);
printf("Reversed string: %s\n", str);
return 0;
}练习题5： 编写一个程序，找出给定整数数组中的最大值和最小值。
#include <stdio.h>
int main() {
int arr[] = {9, 7, 8, 6, Ⅰ1, 5};
int n = sizeof(arr) / sizeof(arr[0]);
int max = arr[0], min = arr[0];
for (int i = 1; i < n; i++) {
if (arr[i] > max) {
max = arr[i];
}
if (arr[i] < min) {
min = arr[i];
}
}
printf("The maximum value in the array is %d\n", max);
printf("The minimum value in the array is %d\n", min);
return 0;
}
