一维数组前缀和
很简单!
未处理alist
n, m = map(int,input().split())
alist = list(map(int,input().split()))
def create(q, n):
res = [0 for i in range(n + 1)]
for i in range(1,n + 1):
res[i] = res[i - 1] + q[i - 1]
return res
res = create(alist, n)
while m:
m -= 1
l, r = map(int,input().split())
print(res[r] - res[l - 1])
预处理alist
n, m = map(int,input().split())
alist = list(map(int,('0 ' + input()).split()))
def create(q, n):
res = [0 for i in range(n + 1)]
for i in range(1,n + 1):
res[i] = res[i - 1] + q[i]
return res
res = create(alist, n)
while m:
m -= 1
l, r = map(int,input().split())
print(res[r] - res[l - 1])