Programming Basics Retest Assault

Programming Basics Retest Assault

ASCII code

AZ 65-90
az 97-122
digits 0-9 48-57

least common divisor

Roll and divide

#include<bits/stdc++.h>
using namespace std;

int gcd(int a,int b)
{
	if(a%b!=0)
	return gcd(b,a%b);
	return b;
}

int main()
{
	cout<<"最大公约数"<<gcd(12,16);
	cout<<"最小公倍数"<<12*16/gcd(12,16)<<endl;
}

prime number code

int isPrime(int n)
{
	if(n<2)
	{
		return 0;
	}
	for(int i=2;i<=sqrt(n);i++)
	{
		if(n%i==0)
		return 0;
	}
	return 1;
}

Judgment of leap year

Ordinary leap year: the Gregorian calendar year is a multiple of 4, and not a multiple of 100, which is an ordinary leap year; century leap year: the Gregorian calendar year is a multiple of hundreds, and must be a multiple of 400 to be a century leap year.

int isrun(int year)
{
	if((year%4==0&&year%100!=0)||year%400==0)
	return 1;
	return 0;
}

triangle area formula

file operation

Functions to read or output a character from a text file