编程题1+(1+2)+(1+2+3) + … + (1+2+3+ … +100)JAVA

public class Sum
{
// private static int s=0;
public static int ss=0;
public int add(int s)
{
for(int j=1;j<=s;j++)
{ ss+=j;
}
return ss;
}
public static void main(String[] args)
{
Sum tt=new Sum();
for(int i=1;i<=100;i++)
{
int mm=tt.add(i);
if (i==100)
{
System.out.println(mm);
}
}
}
}
Result is :
171700

public class Test
{
public static void main(String [] args){
int num,sum=0;
for(int i=1;i<=100;i++){
num=0;
for(int j=1;j<=i;j++){
num+=j;
}
sum+=num;
}
System.out.println(sum);
}
}

class Main(){
public static void main(String[]args){
int sum=0,t=0;
for(int i=1;i<=100;i++){
for(int j=1;j