added graph algorithms

Author: Barbu Paul - Gheorghe

bf_df.cpp

@@ -0,0 +1,84 @@
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+int c[100], viz[100], n, a[100][100];
+
+void bf(int x){
+    c[0] = x;
+    viz[x] = 1;
+    int p = 0;
+    int u = 0;
+
+    while(p<=u){
+        int k = c[p];
+
+        for(int i=1; i<=n; i++){
+            if(1 == a[k][i] && 0 == viz[i]){
+                u++;
+                c[u] = i;
+                viz[i] = 1;
+            }
+        }
+
+        p++;
+    }
+}
+
+void bf_tip(){
+    int i=0;
+
+    while(c[i]){
+        cout<<c[i++]<<' ';
+    }
+}
+
+void init(){
+    for(int i=0; i<=n; i++){
+        c[i] = 0;
+        viz[i] = 0;
+    }
+}
+
+void df(int x){
+    viz[x] = 1;
+    cout<<x<<' ';
+
+    for(int i=1; i<=n; i++){
+        if(a[x][i] && !viz[i]){
+            df(i);
+        }
+    }
+}
+
+int main(){
+    int m, x, y;
+    ifstream f("bf_df.in");
+
+    f>>n>>m;
+    for(int i=0; i<=m; i++){
+        f>>x>>y;
+        a[x][y] = a[y][x] = 1;
+    }
+
+    cout<<"BF:\n";
+
+    for(int i=1; i<=n; i++){
+        bf(i);
+        bf_tip();
+        init();
+        cout<<"\n";
+    }
+
+    cout<<"DF:\n";
+
+    for(int i=1; i<=n; i++){
+        df(i);
+        init();
+        cout<<"\n";
+    }
+
+    f.close();
+}
+

dijkstra.cpp

@@ -0,0 +1,99 @@
+#include <iostream>
+#include <fstream>
+#include <climits>
+
+//#define INT_MAX 1000
+
+using namespace std;
+
+int m, n, a[100][100], x;
+
+ifstream f("graf.txt");
+
+void init_matrice(){
+	for(int i=1; i<=n; i++){
+		for(int j=1; j<=n; j++){
+			//if(i == j){
+			//	a[i][i] = 0;
+			//}
+			//else{
+				a[i][j] = INT_MAX;
+			//}
+		}
+	}
+}
+
+void citire(){
+	int x, y;
+	
+	for(int i=0; i<m; i++){
+		f>>x>>y;
+		f>>a[x][y];
+	}		
+}
+
+/* DIJKSTRA */
+int s[100], d[100], t[100];
+
+void init_dijkstra(int n, int x){
+	s[x] = 1;
+	
+	for(int i=1; i<=n; i++){
+		d[i] = a[x][i];
+		
+		if(a[x][i] != INT_MAX && a[x][i] != 0){
+			t[i] = x;
+		}
+	}
+}
+
+void dijkstra(int x){
+	int minim = INT_MAX, p;
+	
+	for(int i=1; i<n; i++){
+		minim = INT_MAX;
+		for(int j=1; j<=n; j++){
+			if(!s[j] && d[j] < minim){
+				minim = d[j];
+				p = j;
+			}
+		}
+		
+		s[p] = 1;
+		
+		if(minim == INT_MAX){
+			return;
+		}
+		
+		for(int j=1; j<=n; j++){
+			if(d[p] + a[p][j] < d[j] && a[p][j] != INT_MAX){
+				d[j] = d[p] + a[p][j];
+				t[j] = p;
+			}
+		}
+	}
+}
+
+void afisare(int x, int y){
+	if(t[y] != 0){
+		afisare(x, t[y]);
+		cout<<y<<' ';
+	}
+	else{
+		cout<<x<<' ';
+	}
+}
+
+int main(){
+	f>>n>>m;
+	
+	init_matrice();
+	citire();
+	f>>x;
+	init_dijkstra(n, x);
+	
+	dijkstra(x);
+	afisare(x, 1);
+	
+	f.close();
+}

graf_hamiltonian_eulerian_folosind_rw.cpp

@@ -0,0 +1,131 @@
+#include <iostream>
+#include <fstream>
+
+using namespace std;
+
+int st[100], a[100][100], n, m, uz[100], hamiltonian = 0;
+
+
+// GRAF HAMILTONIAN
+int valid(int k){
+    if(k == 1){
+        return 1;
+    }
+
+    if(a[st[k]][st[k-1]]){
+        return 1; //exista muchie intre nodul curent si cel precedent
+    }
+
+    return 0;
+}
+
+void tip(int k){
+    for(int i=1; i<=k; i++){
+        cout<<st[i]<<' ';
+    }
+
+    cout<<"\n";
+}
+
+int sol(int k){
+    if(k == n && a[st[k]][st[1]]){
+        return 1;
+    }
+
+    return 0;
+}
+
+void ch(int k){
+    for(int i=1; i<=n; i++){
+        st[k] = i;
+
+        if(!uz[i] && valid(k)){
+            uz[i] = 1;
+
+            if(sol(k)){
+                hamiltonian = 1;
+                //tip(k);
+                return;
+            }
+            else{
+                ch(k+1);
+            }
+
+            uz[i] = 0;
+        }
+    }
+}
+
+//GRAF EULERIAN
+int grad(int x){
+    int s=0;
+
+    for(int i=1; i<=n; i++){
+        if(a[x][i]){
+            s++;
+        }
+    }
+
+    return s;
+}
+
+int grade_pare(){
+    for(int i=1; i<=n; i++){
+        if(grad(i) % 2 != 0){
+            return 0;
+        }
+    }
+
+    return 1;
+}
+
+//GRAF CONEX
+int conex(){
+    for(int i=1; i<n; i++){
+        for(int j=i+1; j<=n; j++){
+            if(a[i][j] == 0){
+                return 0;
+            }
+        }
+    }
+
+    return 1;
+}
+
+void rw(){
+    for(int k=1; k<=n; k++){
+        for(int i=1; i<=n; i++){
+            if(i != k){
+                for(int j=1; j<=n; j++){
+                    if(j != k && a[i][j] == 0 && j != i){
+                        a[i][j] = a[i][k] * a[k][j];
+                    }
+                }
+            }
+        }
+    }
+}
+
+int main(){
+    int z, v;
+    ifstream f("ghe.in");
+
+    f>>n>>m;
+
+    for(int i=0; i<m; i++){
+        f>>z>>v;
+        a[z][v] = a[v][z] = 1;
+    }
+
+    ch(1);
+
+    int gr_pare = grade_pare();
+    rw();
+
+    cout<<"Hamiltonian: "<<hamiltonian;
+    int eulerian = conex() & gr_pare;
+    cout<<"\nEulerian: "<<eulerian;
+
+
+    f.close();
+}