code commit test 1

.vs/ProjectSettings.json

 {
-  "CurrentProjectSetting": null
+  "CurrentProjectSetting": "Keine Konfigurationen"
 }
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main.cpp

+#include <iostream>
+#include <stdlib.h>
+#include <time.h>
+#include <sys/time.h>
+#include "matrix.h"
+ 
+typedef pair<matrix, long> result;
+ 
+int cut = 64;
+ 
+matrix mult_std(matrix a, matrix b) {
+        matrix c(a.dim(), false, false);
+        for (int i = 0; i < a.dim(); i++)
+                for (int k = 0; k < a.dim(); k++)
+                        for (int j = 0; j < a.dim(); j++)
+                                c(i,j) += a(i,k) * b(k,j);
+       
+        return c;
+}
+ 
+matrix get_part(int pi, int pj, matrix m) {
+        matrix p(m.dim() / 2, false, true);
+        pi = pi * p.dim();
+        pj = pj * p.dim();
+       
+        for (int i = 0; i < p.dim(); i++)
+                for (int j = 0; j < p.dim(); j++)
+                        p(i,j) = m(i + pi,j + pj);
+                       
+        return p;
+}
+ 
+void set_part(int pi, int pj, matrix* m, matrix p) {
+        pi = pi * p.dim();
+        pj = pj * p.dim();
+       
+        for (int i = 0; i < p.dim(); i++)
+                for (int j = 0; j < p.dim(); j++)
+                        (*m)(i + pi,j + pj) = p(i,j);
+}
+ 
+matrix mult_strassen(matrix a, matrix b) {
+        if (a.dim() <= cut)
+                return mult_std(a, b);
+ 
+        matrix a11 = get_part(0, 0, a);
+        matrix a12 = get_part(0, 1, a);
+        matrix a21 = get_part(1, 0, a);
+        matrix a22 = get_part(1, 1, a);
+       
+        matrix b11 = get_part(0, 0, b);
+        matrix b12 = get_part(0, 1, b);
+        matrix b21 = get_part(1, 0, b);
+        matrix b22 = get_part(1, 1, b);
+       
+        matrix m1 = mult_strassen(a11 + a22, b11 + b22);
+        matrix m2 = mult_strassen(a21 + a22, b11);
+        matrix m3 = mult_strassen(a11, b12 - b22);
+        matrix m4 = mult_strassen(a22, b21 - b11);
+        matrix m5 = mult_strassen(a11 + a12, b22);
+        matrix m6 = mult_strassen(a21 - a11, b11 + b12);
+        matrix m7 = mult_strassen(a12 - a22, b21 + b22);
+       
+        matrix c(a.dim(), false, true);
+        set_part(0, 0, &c, m1 + m4 - m5 + m7);
+        set_part(0, 1, &c, m3 + m5);
+        set_part(1, 0, &c, m2 + m4);
+        set_part(1, 1, &c, m1 - m2 + m3 + m6);
+       
+        return c;
+}
+ 
+pair<matrix, long> run(matrix (*f)(matrix, matrix), matrix a, matrix b) {
+        struct timeval start, end;
+       
+        gettimeofday(&start, NULL);
+        matrix c = f(a, b);
+        gettimeofday(&end, NULL);
+        long e = (end.tv_sec * 1000 + end.tv_usec / 1000);
+        long s =(start.tv_sec * 1000 + start.tv_usec / 1000);
+       
+        return pair<matrix, long> (c, e - s);
+}
+ 
+int main() {
+        /* test cut of for strassen
+        /*
+        for (cut = 2; cut <= 512; cut++) {
+                matrix a(512, true, true);
+                matrix b(512, true, true);
+                result r = run(mult_strassen, a, b);
+                cout << cut << " " << r.second << "\n";
+        }
+        */
+       
+        /* performance test: standard and strassen */
+        for (int dim = 0; dim <= 1024; dim += 64) {
+                matrix a(dim, true, false);
+                matrix b(dim, true, false);
+                result std = run(mult_std, a, b);
+                matrix c(dim, true, true);
+                matrix d(dim, true, true);
+                result strassen = run(mult_strassen, c, d);
+                cout << dim << " " << std.second << " " << strassen.second << "\n";
+        }
+}
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matrix.cpp

+#include <iostream>
+#include <vector>
+#include <stdlib.h>
+#include <time.h>
+#include "matrix.h"
+using namespace std;
+ 
+matrix::matrix(int dim, bool random, bool strassen) : dim_(dim) {
+        if (strassen) {
+                int dim2 = 2;
+                while (dim2 < dim)
+                        dim2 *= 2;
+                dim_ = dim2;
+        }
+       
+        data_ = new int[dim_ * dim_];
+        if (!random) return;
+ 
+        for (int i = 0; i < dim_ * dim_; i++)
+                data_[i] = rand() % 10;
+}
+ 
+void matrix::print() {
+        for (int i = 0; i < dim_; i++) {
+                for (int j = 0; j < dim_; j++)
+                        cout << (*this)(i,j) << " ";
+                cout << "\n";
+        }
+        cout << "\n";
+}
+ 
+matrix matrix::operator+(matrix b) {
+        matrix c(dim_, false, false);
+        for (int i = 0; i < dim_; i++)
+                for (int j = 0; j < dim_; j++)
+                        c(i,j) = (*this)(i,j) + b(i,j);
+               
+        return c;
+}
+ 
+matrix matrix::operator-(matrix b) {
+        matrix c(dim_, false, false);
+        for (int i = 0; i < dim_; i++)
+                for (int j = 0; j < dim_; j++)
+                        c(i,j) = (*this)(i,j) - b(i,j);
+               
+        return c;
+}
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matrix.h

+#ifndef MATRIX_H
+#define MATRIX_H
+ 
+#include <vector>
+using namespace std;
+ 
+class matrix
+{
+public:
+    matrix(int dim, bool random, bool strassen);
+   
+    inline int dim() {
+                        return dim_;
+                }
+                inline int& operator()(unsigned row, unsigned col) {
+                        return data_[dim_*row + col];
+                }
+ 
+                inline int operator()(unsigned row, unsigned col) const {
+                        return data_[dim_*row + col];
+                }
+               
+                void print();
+                matrix operator+(matrix b);
+                matrix operator-(matrix b);
+ 
+private:
+    int dim_;
+    int* data_;
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