Tasks

sergeeva/gen_binary.py

@@ -0,0 +1,11 @@
+k = 3
+def gen_bin(a,p):
+	if p < k:
+		a[p] = 0
+		gen_bin(a, p+1)
+		a[p] = 1
+		gen_bin(a, p+1)
+	else:
+		print(a)
+
+gen_bin([0 for i in range (k)], 0)

sergeeva/generators/allvectors.py

@@ -0,0 +1,16 @@
+infile = open('allvectors.in', 'r')
+outfile = open('allvectors.out', 'w')
+n = int(infile.readline().strip())
+
+a=[0]*n
+def gen_bin(a,p):
+    if p < n:
+        a[p] = 0
+        gen_bin(a, p+1)
+        a[p] = 1
+        gen_bin(a, p+1)
+    else:
+        outfile.write(str(''.join([str(i) for i in a])) + '\n')
+gen_bin(a,0)
+infile.close()
+outfile.close()

sergeeva/generators/choose.py

@@ -0,0 +1,20 @@
+infile = open('choose.in', 'r')
+outfile = open('choose.out', 'w')
+
+n, k = [int(i) for i in infile.readline().split()]
+seq=range(1,n+1)
+
+def choose(seq, k):
+    if k == 0:
+        yield []
+    else:
+        for i, x in enumerate(seq):
+            for c in choose(seq[i+1:], k-1):
+                yield [x] +c
+
+for i in choose(seq, k):
+    outfile.write(str.join(' ', (str(j) for j in i)) + '\n')
+
+infile.close()
+outfile.close()
+

sergeeva/generators/permutations1.py

@@ -0,0 +1,22 @@
+infile = open('permutations.in', 'r')
+outfile = open('permutations.out', 'w')
+
+n = int(infile.readline().strip())
+seq=range(1,n+1)
+
+ans=[]
+
+def permutation(seq, i):
+    if i == len(seq)-1:
+        ans.append(str(''.join([str(i) for i in seq])))
+    else:
+        for j in range(i, len(seq)):
+            seq[i], seq[j] = seq[j], seq[i]
+            permutation(seq, i+1)
+            seq[i], seq[j] = seq[j], seq[i] 
+
+permutation(seq, 0)
+for i in sorted(ans):
+	outfile.write(str(' '.join([str(j) for j in i])+'\n'))
+infile.close()
+outfile.close()

sergeeva/generators/permutations2.py

@@ -0,0 +1,20 @@
+#permutations code from class work
+
+infile = open('permutations.in', 'r')
+outfile = open('permutations.out', 'w')
+
+n = int(infile.readline().strip())
+def gen_perm(a, p):
+	if p < n:
+		for i in range(1, n+1):
+			if i not in a:
+				a[p] = i
+				gen_perm(a, p+1) 
+				a[p] = 0
+	else:
+		outfile.write(str.join(' ', (str(i) for i in a))+'\n')
+
+gen_perm([0 for i in range (n)], 0)
+
+infile.close()
+outfile.close()

sergeeva/generators/vectors.py

@@ -0,0 +1,29 @@
+import re
+infile = open('vectors.in', 'r')
+outfile = open('vectors.out', 'w')
+
+n = int(infile.readline().strip())
+
+a = [0]*n
+all_bin=[]
+def gen_bin(a,p):
+	if p < n:
+		a[p] = 0
+		gen_bin(a, p+1)
+		a[p] = 1
+		gen_bin(a, p+1)
+	else:
+		all_bin.append(str(''.join([str(i) for i in a])))
+
+gen_bin(a,0)
+
+ones=[]
+for i in all_bin:
+	for match in re.findall('11', i):
+		ones.append(i)
+ans=sorted(list(set(all_bin).difference(set(ones))))
+
+outfile.write(str(len(ans))+'\n')
+outfile.write(str('\n'.join([str(i) for i in ans])))
+infile.close()
+outfile.close()

sergeeva/graphs/comp.py

@@ -0,0 +1,41 @@
+from collections import deque
+
+infile = open('components.in', 'r')
+outfile = open('components.out', 'w')
+
+n,e = [int(i) for i in infile.readline().split()] 
+
+#edgelist
+edges=[] 
+for i in range(e):
+    edges.append([int(j) for j in infile.readline().split()])
+
+#neighbours
+from collections import defaultdict
+neighbours = defaultdict(lambda: defaultdict(lambda: 0))
+for v1, v2 in edges:
+    neighbours[v1][v2] += 1
+    neighbours[v2][v1] += 1
+
+def dfs():
+    num_component ={}
+    comp = 0
+    for i in range(1, n+1):
+        if i not in num_component:
+            comp += 1
+            num_component[i] = comp
+            queue = deque([i])
+            while len(queue) > 0:
+                for v in neighbours[queue[0]]:
+                    if v not in num_component:
+                        num_component[v] = comp
+                        queue.append(v)
+                queue.popleft()
+    outfile.write(str(comp)+ '\n')
+    for i in num_component.values():
+        outfile.write(str(i)+' ')
+dfs()
+
+
+infile.close()
+outfile.close()

sergeeva/graphs/pathbge1.py

@@ -0,0 +1,44 @@
+infile = open('pathbge1.in', 'r')
+outfile = open('pathbge1.out', 'w')
+
+n,e = [int(i) for i in infile.readline().split()] 
+
+#edgelist
+edges=[] 
+for i in range(e):
+    edges.append([int(j) for j in infile.readline().split()])
+
+#linking edges
+def link(u, v):
+    if u not in graph:
+        graph[u] = {}
+    (graph[u])[v] = 1
+    if v not in graph:
+        graph[v] = {}
+    (graph[v])[u] = 1
+    return graph
+
+graph = {}
+for (x,y) in edges: 
+    link(x,y)
+dist = {} #distance
+
+def bfs (s, v):
+    q = [s] #queue
+    dist[s] = 0
+    while len(q) > 0:
+        current = q.pop(0)
+        for i in graph[current].keys():
+            if i not in dist:
+                dist[i] = dist[current] + 1
+                if i == v:
+                    return dist[v]
+                q.append(i)
+    return dist
+
+bfs(1,n+1)
+for j in dist.values():
+    outfile.write(str(j) + ' ')
+
+infile.close()
+outfile.close()

sergeeva/graphs/pathmgep.py

@@ -0,0 +1,35 @@
+infile = open('pathmgep.in', 'r')
+outfile = open('pathmgep.out', 'w')
+
+n, S, F = [int(i) for i in infile.readline().split()] 
+
+dist = []
+
+sum=0
+for line in infile.read().splitlines():
+    values = [int(i) for i in line.split()]
+    dist.append(values)
+    for i in values:
+    	if i>0:
+    		sum+=i
+
+for i in range(n):
+    for j in range(n):
+       	if dist[i][j] == -1:
+       		dist[i][j] = sum +1
+
+def floyd(dist): 
+    for k in range(n):
+        for i in range(n):
+            for j in range(n):
+                dist[i][j] = min(dist[i][j], (dist[i][k] + dist[k][j]))
+
+
+floyd(dist)
+
+if dist[S-1][F-1]>=sum:
+	dist[S-1][F-1]=-1
+
+outfile.write(str(dist[S-1][F-1]))
+infile.close()
+outfile.close()

sergeeva/graphs/pathsg.py

@@ -0,0 +1,33 @@
+#floyd 
+infile = open('pathsg.in', 'r')
+outfile = open('pathsg.out', 'w')
+
+n,e = [int(i) for i in infile.readline().split()] 
+
+dist = [[float('inf') for i in range(n)] for j in range(n)]
+
+sum=0
+for i in range(e):
+    u, v, weight = [int(x) for x in infile.readline().split()]
+    dist[u-1][v-1] = weight
+    sum += weight
+
+for i in range(n):
+    for j in range(n):
+        if i == j:
+            dist[i][j] = 0
+        elif dist[i][j] == float('inf'):
+            dist[i][j] = sum +1
+
+def floyd(dist): 
+    for k in range(n):
+        for i in range(n):
+            for j in range(n):
+                dist[i][j] = min(dist[i][j], (dist[i][k] + dist[k][j]))
+
+floyd(dist)
+
+for row in dist:
+    outfile.write(' '.join(str(i) for i in row) + '\n')
+infile.close()
+outfile.close()

sergeeva/minimum.py

@@ -0,0 +1,6 @@
+a = [10,5,9,7]
+m = a[0]
+for i in a:
+	if i < m:
+		m = i
+print(m)