B. New Year’s Number
time limit per test2 seconds
memory limit per test256 megabytes
inputstandard input
outputstandard output
Polycarp remembered the 2020-th year, and he is happy with the arrival of the new 2021-th year. To remember such a wonderful moment, Polycarp wants to represent the number n as the sum of a certain number of 2020 and a certain number of 2021.
For example, if:
n=4041, then the number n can be represented as the sum 2020+2021;
n=4042, then the number n can be represented as the sum 2021+2021;
n=8081, then the number n can be represented as the sum 2020+2020+2020+2021;
n=8079, then the number n cannot be represented as the sum of the numbers 2020 and 2021.
Help Polycarp to find out whether the number n can be represented as the sum of a certain number of numbers 2020 and a certain number of numbers 2021.
Input
The first line contains one integer t (1≤t≤104) — the number of test cases. Then t test cases follow.
Each test case contains one integer n (1≤n≤106) — the number that Polycarp wants to represent as the sum of the numbers 2020 and 2021.
Output
For each test case, output on a separate line:
“YES” if the number n is representable as the sum of a certain number of 2020 and a certain number of 2021;
“NO” otherwise.
You can output “YES” and “NO” in any case (for example, the strings yEs, yes, Yes and YES will be recognized as positive).
Example
inputCopy
5
1
4041
4042
8081
8079
outputCopy
NO
YES
YES
YES
NO
暴力循环即可，或者进行第二重的循环优化即可
第一种：
双重循环：
#include<bits/stdc++.h>
using namespace std;
int main(){
int n;
int t;
cin>>t;
while(t--)
{
bool flag=false;
cin>>n;
for(int i=0;i<=496;i++)
for(int j=0;j<=495;j++)
if((i*2020+j*2021)==n)
{
flag=true; break;}
if(flag)
cout<<"YES"<<endl;
else
{
cout<<"NO"<<endl;
}
flag=false;
}
// system("pause");
}
第二种的优化：
#include<bits/stdc++.h>
using namespace std;
int main(){
int n;
int t;
cin>>t;
while(t--)
{
bool flag=false;
cin>>n;
for(int i=0;i<=496;i++)
if((n-i*2020)%2021==0&&(n-i*2020)>=0)
{
flag=true; break;}
if(flag)
cout<<"YES"<<endl;
else
{
cout<<"NO"<<endl;
}
flag=false;
}
//system("pause");
}