Buggy python submission (verdict: Runtime Error):
n,m=map(int,input().split())
e=[]
for i in range(m):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    g=[[] for _ in range(n)]
    for j in range(m):
        if i==j:
            continue
        g[e[j][0]-1].append(e[j][1])
        g[e[j][1]-1].append(e[j][0])
    visited=[0]*n
    visited[0]=1
    q=[1]
    while len(q)>0:
        a=pop(q)
        visited[a-1]=1
        for k in g[a-1]:
            if visited[k-1]==0:
                q+=[k]
    if sum(visited)!=n:
        ans+=1
print(ans)
                    


Fixed submission:
n,m=map(int,input().split())
e=[]
for i in range(m):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    g=[[] for _ in range(n)]
    for j in range(m):
        if i==j:
            continue
        g[e[j][0]-1].append(e[j][1])
        g[e[j][1]-1].append(e[j][0])
    visited=[0]*n
    visited[0]=1
    q=[1]
    while len(q)>0:
        a=q.pop(0)
        visited[a-1]=1
        for k in g[a-1]:
            if visited[k-1]==0:
                q+=[k]
    if sum(visited)!=n:
        ans+=1
print(ans)

Buggy python submission (verdict: Time Limit Exceeded):
n,m=map(int,input().split())
e=[]
for i in range(m):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    nall=[]
    for j in range(m):
        if i==j:
            continue
        nall.append(e[j])
    visited=[0]*n
    visited[0]=1
    t=[1]
    while len(t)>0:
        tmp=[]
        ntmp=[]
        for p in t:
            visited[p-1]=1
            for q in nall:
                if q[0]==p:
                    if visited[q[1]-1]==0:
                        tmp.append(q[1])
                        visited[q[1]-1]=1
                elif q[1]==p:
                    if visited[q[0]-1]==0:
                        tmp.append(q[0])
                        visited[q[0]-1]=1
                else:
                    if visited[q[0]-1]==0 or visited[q[1]-1]==0:
                        ntmp.append(q)
        t=tmp
        nall=ntmp
    if sum(visited)!=n:
        ans+=1
print(ans)
                    


Fixed submission:
n,m=map(int,input().split())
e=[]
for i in range(m):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    g=[[] for _ in range(n)]
    for j in range(m):
        if i==j:
            continue
        g[e[j][0]-1].append(e[j][1])
        g[e[j][1]-1].append(e[j][0])
    visited=[0]*n
    visited[0]=1
    q=[1]
    while len(q)>0:
        a=q.pop(0)
        visited[a-1]=1
        for k in g[a-1]:
            if visited[k-1]==0:
                q+=[k]
    if sum(visited)!=n:
        ans+=1
print(ans)

Buggy python submission (verdict: Runtime Error):
n,m=map(int,input().split())
e=[]
for i in range(n):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    nall=[]
    for j in range(m):
        if i==j:
            continue
        nall.append(e[j])
    visited=[0]*n
    visited[0]=1
    t=[1]
    while len(t)>0:
        tmp=[]
        ntmp=[]
        for p in t:
            visited[p-1]=1
            for q in nall:
                if q[0]==p:
                    if visited[q[1]-1]==0:
                        tmp.append(q[1])
                        visited[q[1]-1]=1
                elif q[1]==p:
                    if visited[q[0]-1]==0:
                        tmp.append(q[0])
                        visited[q[0]-1]=1
                else:
                    if visited[q[0]-1]==0 and visited[q[1]-1]==0:
                        ntmp.append(q)
        t=tmp
        nall=ntmp
    if sum(visited)!=n:
        ans+=1
print(ans)
                    


Fixed submission:
n,m=map(int,input().split())
e=[]
for i in range(m):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    g=[[] for _ in range(n)]
    for j in range(m):
        if i==j:
            continue
        g[e[j][0]-1].append(e[j][1])
        g[e[j][1]-1].append(e[j][0])
    visited=[0]*n
    visited[0]=1
    q=[1]
    while len(q)>0:
        a=q.pop(0)
        visited[a-1]=1
        for k in g[a-1]:
            if visited[k-1]==0:
                q+=[k]
    if sum(visited)!=n:
        ans+=1
print(ans)

Buggy python submission (verdict: Runtime Error):
n,m=map(int,input().split())
e=[]
for i in range(n):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    nall=[]
    for j in range(m):
        if i==j:
            continue
        nall.append(e[j])
    visited=[0]*n
    t=[1]
    while len(t)>0:
        tmp=[]
        ntmp=[]
        for p in t:
            visited[p-1]=1
            for q in nall:
                if q[0]==p:
                    if visited[q[1]-1]==0:
                        tmp.append(q[1])
                        visited[q[1]-1]=1
                elif q[1]==p:
                    if visited[q[0]-1]==0:
                        tmp.append(q[0])
                        visited[q[0]-1]=1
                else:
                    ntmp.append(q)
        t=tmp
        nall=ntmp
    if sum(visited)!=n:
        ans+=1
print(ans)
                    

Fixed submission:
n,m=map(int,input().split())
e=[]
for i in range(m):
    e.append(list(map(int,input().split())))
ans=0
for i in range(m):
    g=[[] for _ in range(n)]
    for j in range(m):
        if i==j:
            continue
        g[e[j][0]-1].append(e[j][1])
        g[e[j][1]-1].append(e[j][0])
    visited=[0]*n
    visited[0]=1
    q=[1]
    while len(q)>0:
        a=q.pop(0)
        visited[a-1]=1
        for k in g[a-1]:
            if visited[k-1]==0:
                q+=[k]
    if sum(visited)!=n:
        ans+=1
print(ans)