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divsum.java
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divsum.java
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import java.io.*;
import java.util.*;
public class divsum
{
private static Reader in;
private static PrintWriter out;
public static void main (String [] args) throws IOException {
int MAX = 500000;
int[] divSum = new int [MAX + 1];
for (int i = 1; i <= MAX; i++)
for (int j = i*2; j <= MAX; j += i)
divSum [j] += i;
in = new Reader ();
out = new PrintWriter (System.out, true);
int t = in.nextInt ();
while (t-->0)
out.println (divSum[in.nextInt()] );
}
}
/** Faster input **/
class Reader {
final private int BUFFER_SIZE = 1 << 16;
private DataInputStream din;
private byte[] buffer;
private int bufferPointer, bytesRead;
public Reader(){
din=new DataInputStream(System.in);
buffer=new byte[BUFFER_SIZE];
bufferPointer=bytesRead=0;
}
public Reader(String file_name) throws IOException{
din=new DataInputStream(new FileInputStream(file_name));
buffer=new byte[BUFFER_SIZE];
bufferPointer=bytesRead=0;
}
public String readLine() throws IOException{
byte[] buf=new byte[64]; // line length
int cnt=0,c;
while((c=read())!=-1){
if(c=='\n')break;
buf[cnt++]=(byte)c;
}
return new String(buf,0,cnt);
}
public int nextInt() throws IOException{
int ret=0;byte c=read();
while(c<=' ')c=read();
boolean neg=(c=='-');
if(neg)c=read();
do{ret=ret*10+c-'0';}while((c=read())>='0'&&c<='9');
if(neg)return -ret;
return ret;
}
public long nextLong() throws IOException{
long ret=0;byte c=read();
while(c<=' ')c=read();
boolean neg=(c=='-');
if(neg)c=read();
do{ret=ret*10+c-'0';}while((c=read())>='0'&&c<='9');
if(neg)return -ret;
return ret;
}
public double nextDouble() throws IOException{
double ret=0,div=1;byte c=read();
while(c<=' ')c=read();
boolean neg=(c=='-');
if(neg)c = read();
do {ret=ret*10+c-'0';}while((c=read())>='0'&&c<='9');
if(c=='.')while((c=read())>='0'&&c<='9')
ret+=(c-'0')/(div*=10);
if(neg)return -ret;
return ret;
}
private void fillBuffer() throws IOException{
bytesRead=din.read(buffer,bufferPointer=0,BUFFER_SIZE);
if(bytesRead==-1)buffer[0]=-1;
}
private byte read() throws IOException{
if(bufferPointer==bytesRead)fillBuffer();
return buffer[bufferPointer++];
}
public void close() throws IOException{
if(din==null) return;
din.close();
}
}