由于笔者Python能力有限,观点可能较为片面

在享受Python带来的便捷性的同时,我们发现Python无法像C++一样按照空格或者回车单独读入数据,而只能按照行读入。所以当我们遇到一些不够严谨的数据时,Python无法像C++一样正常读入数据。

  • example:

P1719 最大加权矩形

看一个80分代码:

n = int(input())
f = [[0 for i in range(200)] for j in range(200)]
for i in range(n) :
    tmp = input().split()
    for j in range(n):
        f[i][j] = -f[i - 1][j - 1] + f[i][j - 1] + f[i - 1][j] + int(tmp[j])
maxn = 0
for i in range(n):
    for j in range(i, n):
        maxtt = 0
        for k in range(n):
            tmp = f[j][k] - f[i - 1][k] - f[j][k - 1] + f[i - 1][k - 1]
            maxtt += tmp
            if maxtt > maxn: maxn = maxtt
            if maxtt < 0: maxtt = 0
print(maxn)

第五个数据点,数据没有按照 nn 列输入,而这会导致这个代码少读很多行。

所以需要将读入部分作一个小修改,下面是我的代码。

n = int(input())
f = [[0 for i in range(200)] for j in range(200)]
mp = [[0 for i in range(200)] for j in range(200)]
cnt = 0
while(True):
    try:
        tmp = input().split()
        for i in tmp:
            mp[cnt // n][cnt % n] = int(i) 
            cnt += 1
    except:
        break
for i in range(n) :
    for j in range(n):
        f[i][j] = -f[i - 1][j - 1] + f[i][j - 1] + f[i - 1][j] + mp[i][j]
maxn = 0
for i in range(n):
    for j in range(i, n):
        maxtt = 0
        for k in range(n):
            tmp = f[j][k] - f[i - 1][k] - f[j][k - 1] + f[i - 1][k - 1]
            maxtt += tmp
            if maxtt > maxn: maxn = maxtt
            if maxtt < 0: maxtt = 0
print(maxn)