add mathematics folder

Author: sandromirr

Mathematics/02-mathematics.pdf

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+#include <iostream>
+using namespace std;
+
+int zeros(int number){
+    int zero = 0;
+
+    for(int i = 5 ; i <= number ; i*=5){
+        zero += (number / i);
+    }
+
+    return zero;
+}
+
+int main(){
+    int t,x;
+    cin >> t;
+    while(t--){
+        cin >> x;
+        cout << zeros(x) << endl;
+    }
+}

Mathematics/1401.cpp

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+#include <iostream>
+#include <cmath>
+#include <iomanip>
+#define M_PI 3.14159265358979323846
+using namespace std;
+
+float solve(float R,int n){
+    return R/(1.0/sin(M_PI/n)+1.0);
+}
+
+int main(){
+    int t,n,cnt = 1;
+    float R;
+    cin >> t;
+    while(t--){
+        cin >> R >> n;
+        cout << "Scenario #" << cnt++ << endl; 
+        cout << setprecision(3) << fixed << solve(R,n) << endl;
+    }
+    cout << endl;
+}

Mathematics/1779.cpp

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+#include <iostream>
+#include <cmath>
+#include <iomanip>
+using namespace std;
+
+const double pi = 3.141592653589793;
+
+double distance(double x1,double y1,double x2,double y2){
+    return sqrt(pow(x1 - x2,2) + pow(y1 - y2,2)); 
+}
+
+int main(){
+    double x1,x2,x3,y1,y2,y3;
+    while(cin >> x1 >> y1 >> x2 >> y2 >> x3 >> y3){
+        double d1 = distance(x1,y1,x2,y2);
+        double d2 = distance(x2,y2,x3,y3);
+        double d3 = distance(x1,y1,x3,y3);
+        double s = sqrt((d1 + d2 + d3) * (d1 + d2 - d3) * (d2 + d3 - d1) * (d1 + d3 - d2));
+        double r = (d1 * d2 * d3) / s;
+        double area = 2 * pi * r;
+        printf("%4.2f\n", area);
+    }
+}

Mathematics/2242.cpp

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+#include <iostream>
+#include <math.h>
+using namespace std;
+
+bool isPrime(int number){
+    for(int i = 2 ; i <= sqrt((double)number) ; i++){
+        if(number % i == 0){
+            return false;
+        }
+    }
+
+    return true;
+}
+
+int main(){
+    int number;
+    while(cin >> number){
+        if(number == 0) break;
+        for(int i = 2 ; i <= number / 2 ; i++){
+            int flags = 0;
+            if(isPrime(i)){
+                flags++;
+            }else continue;
+            if(isPrime(number - i)){
+                flags++;
+            }
+            if(flags == 2){
+                cout << number << " = " << i << " + " << (number - i) << endl;
+                break;
+            }
+        }
+    }
+}