first question
Find the greatest common divisor and the least common multiple. Enter two positive integers m and n (m≤1000, n≤1000), and find the greatest common divisor and least common multiple. Try to write the corresponding program.
#include<stdio.h>
int main() {
int m, n,a,b,c;
printf("请输入两个正整数m和n:(m<=1000,n<=1000，m>=n)\n");
scanf("%d %d", &m, &n);
a = m;
b = n;
while (b != 0) {
c = a % b;
a = b;
b = c;
}
printf("最大公约数为%d\n", a);
printf("最小公倍数为%d\n", m * n / a);
}
Second question
Use the function to verify Goldbach’s conjecture: any even number not less than 6 can be expressed as the sum of two odd prime numbers. For example, 6=3+3, 8=3+5,..., 18=5+13. Express the even numbers between 6 and 100 as the sum of two prime numbers, and print 5 groups on one line when printing. Try to write the corresponding program.
#include <stdio.h>
int prime(int n);
int main()
{
int m, i, a = 0;
for (int n = 6; n <= 100; n += 2) {
for (i = 3; i < n; i += 2) {
m = n - i;
if (prime(m) == 1 && prime(i) == 1) {
printf("%d=%d+%d ", n, i, m);
a++;
if (a % 5 == 0)
printf("\n");
break;
}
}
}
return 0;
}
int prime(int n)
{
int i;
for (i = 2; i < n && (n % i != 0); i++);
return n == i ? 1 : 0; //判断是否为素数，是返回1，否返回0
}
Third question
Find the number that appears the most in a batch of integers. Enter a positive integer n (n≤1000), then enter n integers, analyze each digit of each integer, and find the number with the most occurrences. For example, if you enter 3 integers 1234, 2345, 3456, the most frequently occurring numbers are 3 and 4, both appearing 3 times. Try to write the corresponding program.
#include<stdio.h>
int main()
{
int n,t=0;
int b[10];
int a,c;
for (int i = 0; i < 10; i++) {
b[i] = 0;
}
printf("你想要输入几个整数:(n<=1000)\n");
scanf("%d", &n);
printf("请输入这%d个整数(以空格隔开):\n",n);
for (int i = 1; i <= n; i++) {
scanf("%d", &a);
if (a == 0) b[0] == 0;
while (a != 0) {
c = a % 10;
a /= 10;
b[c]++;
}
}
for (int i = 0; i < 10; i++)
{
if (b[i] > t)
t = b[i];
}
for (int i = 0; i < 10; i++)
{
if (t==b[i])
printf(" %d", i);
}
return 0;
}
Fourth question
#include<stdio.h>
int main()
{
int n,m=0;
int a[6][6];
printf("请输入n:(1<=n<=6)\n");
scanf("%d", &n);
printf("输入%d阶方阵\n", n);
for (int i = 0; i < n; i++) {
for (int j = 0; j < n; j++) {
scanf("%d", &a[i][j]);
}
}
for (int i = 0; i < n; i++) {
for (int j = 0; j < i + 1; j++)
if (a[i][j] == 0)
m++;
}
if (m != 0)
printf("YES");
else
printf("NO");
}
to sum up
The above is the C language-related homework exercises and the author's own thinking, I hope to help everyone.