public static void main(String[] args) { double d = 0.0; int x = 1; for (int i = 1; i <= 2000; i++,x*=-1) { d += 1D/(2*i-1)*x*4; } System.out.println(d); }
public static void main(String[] args) { double pi = 0.0; int n = 1; for (int i = 0; i < 2000; i++){ pi = pi + n / (double)(i * 2 + 1.0); n = -n; } pi = pi * 4; System.out.println(pi); }
public class TestPI { public static void main(String[] args) { double sum = 0; double PI; for(float i=1; i<=2000; i++) { sum += ((Math.pow(-1,i+1))*(1/(2*i-1))); } PI = sum * 4; System.out.println(PI); } }这个可以吧,行不?
public static void main(String[] args) {
double d = 0.0;
int x = 1;
for (int i = 1; i <= 2000; i++,x*=-1) {
d += 1D/(2*i-1)*x*4;
}
System.out.println(d);
}
double pi = 0.0;
int n = 1;
for (int i = 0; i < 2000; i++){
pi = pi + n / (double)(i * 2 + 1.0);
n = -n;
}
pi = pi * 4;
System.out.println(pi);
}
public class TestPI {
public static void main(String[] args) {
double sum = 0;
double PI;
for(float i=1; i<=2000; i++) {
sum += ((Math.pow(-1,i+1))*(1/(2*i-1)));
}
PI = sum * 4;
System.out.println(PI);
}
}这个可以吧,行不?
boolean flag=false;
double increase=2;
double currentNum=1;
for(int i=0;i<2000;i++){
currentNum+=increase;
if(flag)
pi+=1/currentNum;
else
pi-=1/currentNum;
flag=!flag;
}
pi=pi*4;