ZOJ 3427 Array Slicing （scanf使用）

• 空白字符: scanf在读入时会忽略下一个非空白字符之前的所有空白字符  空白字符包含 ‘ ‘‘\t‘, ‘\n‘, ‘\v‘, ‘\f‘, ‘\r
  
• 非%的非空白字符: 输入时必须严格匹配这些字符  否则会读入失败
• 格式说明符%: 说明读取数据的类型或读取规则  %[*][width][length]specifier

int main()
{
    char s[500];
    int n;
    scanf("%s%n", s, &n);
    printf("%s  %d\n", s, n);
    //输入hello
    //输出hello 5
    return 0;
}

int main()
{
    int n;
    printf("hello%n", &n);
    printf(" %d\n", n);
    //输出hello 5
    return 0;
}

specifier可以是[...]、[^...]这两种正则表达式  

[...]表示读取括号中包含的字符 遇到其他字符就结束这个specifier

int main()
{
    char s[500];
    int n;
    scanf(" %[0-9]%n", s, &n);//%[0-9]只读取数字  遇到非数字结束
    printf("%s %d\n", s, n);
    scanf(" %[ab]%n", s, &n);
    printf("%s %d\n", s, n);
    //输入"   12345abc"  前面有三个空格
    //输出12345 8  ab 2
    return 0;
}

[^...]表示读取除括号中字符之外的所有字符 遇到括号中的字符就结束这个specifier

当然这些东西sscanf也适用

感觉预习了scanf之后这个题的输入就很好处理了  直接用list的splice函数就行了

#include <bits/stdc++.h>
using namespace std;
char s[5000], *ps;

int main()
{
    list<int> a, b;
    int l, r, n, v;
    list<int>::iterator it;
    while(~scanf(" [ %d : %d ]%[^\n]", &l, &r, s))
    {
        b.clear();
        ps = s;
        while(sscanf(ps, "%*[^-0-9]%d%n", &v, &n) > 0)
        {
            //过滤掉非'-'和数字再读入一个数
            //n记录scanf读了多少个字符
            ps = ps + n;  //读了n个字符所以要前进n位
            b.push_back(v);
        }

        advance(it = a.begin(), l);
        while(l < r)
        {
            printf("%d%s", *it, l < r - 1 ? ", " : "");
            it = a.erase(it);
            l++;
        }
        puts("");
        a.splice(it, b);
    }
    return 0;
}

Array slicing is an operation that extracts certain elements from an array and packages them as another array. Now you‘re asked to implements the array slicing operations for a new programming language -- eggache* (pronounced "eggache star"). The grammar of array slicing in eggache* is:

Input

There is only one case for this problem, which contains about 50 lines of array slicing operations. It‘s guaranteed that all operations are valid and the absolute values of all integers never exceed 100. The array is empty ([]) before the first operation.

Output

The output produced by array slicing operations in the eggache* programming language.

Sample Input

[ 0 : 0] = 1 2 3 4 5 6 7 8 9
[ 1 : 1] = -1
[ 1 : 1] =
[ 0 : 8] = 9 8 7 6 5 4 3 2 1
[ 2 : 8] = -2, -3, -5, -7 
[ 0 : 9] = 000
[ 0 : 1] = 1, 2, 8
[ 2 : 2] = 4
[ 0 : 4] =

Sample Output

1, -1, 2, 3, 4, 5, 6, 7
7, 6, 5, 4, 3, 2
9, 8, -2, -3, -5, -7, 1, 8, 9
0

1, 2, 4, 8