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import sys
from collections import deque
class Edge:
    def __init__(self, to, rev, capacity):
        self.to = to
        self.rev = rev
        self.capacity = capacity
class MinCut:
    def __init__(self, n):
        self.size = n
        self.graph = [[] for _ in range(n)]
    
    def add_edge(self, fr, to, cap):
        forward = Edge(to, len(self.graph[to]), cap)
        backward = Edge(fr, len(self.graph[fr]), 0)
        self.graph[fr].append(forward)
        self.graph[to].append(backward)
    
    def bfs_level(self, s, t, level):
        q = deque()
        level[:] = [-1]*self.size
        level[s] = 0
        q.append(s)
        while q:
            v = q.popleft()
            for edge in self.graph[v]:
                if edge.capacity > 0 and level[edge.to] == -1:
                    level[edge.to] = level[v] + 1
                    q.append(edge.to)
                    if edge.to == t:
                        return
        return
    
    def dfs_flow(self, v, t, upTo, iter_, level):
        if v == t:
            return upTo
        for i in range(iter_[v], len(self.graph[v])):
            edge = self.graph[v][i]
            if edge.capacity > 0 and level[v] < level[edge.to]:
                d = self.dfs_flow(edge.to, t, min(upTo, edge.capacity), iter_, level)
                if d > 0:
                    edge.capacity -= d
                    self.graph[edge.to][edge.rev].capacity += d
                    return d
            iter_[v] +=1
        return 0
    
    def min_cut(self, s, t):
        level = [-1]*self.size
        self.bfs_level(s, t, level)
        if level[t] == -1:
            return 0
        iter_ = [0]*self.size
        flow = self.dfs_flow(s, t, float('inf'), iter_, level)
        return flow
def main():
    n, m = map(int, sys.stdin.readline().split())
    a = list(map(int, sys.stdin.readline().split()))
    edges = [[] for _ in range(n)]
    for _ in range(m):
        u, v = map(int, sys.stdin.readline().split())
        u -=1
        v -=1
        edges[u].append(v)
        edges[v].append(u)
    
    size = 2 * n
    source = 0
    sink = 2 * n -1
    mc = MinCut(size)
    for i in range(n):
        mc.add_edge(source, 2*i, a[i])
        mc.add_edge(2*i +1, sink, 1)
    
    for u in range(n):
        for v in edges[u]:
            mc.add_edge(2*u, 2*v, 1)
            mc.add_edge(2*v, 2*u, 1)
    
    min_flow = mc.min_cut(source, sink)
    print(min_flow)
if __name__ == "__main__":
    main()

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