g++ stdvpi.cpp -o stdvpi && ./stdvpi

stdvpi.cpp

#include "stdio.h"
#include <iostream>
#include <cstdlib> 
#include <cmath>
#include <vector>
#include <numeric>
using namespace std;
int random1 = 1000;
int psize = 1000000;

std::vector< int > piarray;
unsigned int n = 0;
static void picalc(){
	unsigned int i = 0;
	unsigned int j = 0;
	while(j <= random1){
		float x = rand(); 
		float y = rand();
		//cout << x;
		//cout << y; 
		float distancesquared = pow(x, 2) + pow(y, 2);
		if(distancesquared <= pow(1,2)){
			i = i + 1;
		};
		j = j + 1;
	};
	int pi = 4*(i/(j-1));
	piarray.push_back(pi);
};


int main(){
cout << "Enter number of random entries: \n";
cin >> random1;
cout << "Enter number of entries in array: \n";
cin >> psize;
while(piarray.size() < psize){
	picalc();
};
float pimean = 1.0 * std::accumulate(piarray.begin(), piarray.end(), 0LL) / piarray.size();
cout << pimean;
printf("\nterminated");
return 0;
};