CodeForces Petya and Java strcmp的使用

B - Petya and Java
Time Limit:2000MS Memory Limit:262144KB 64bit IO Format:%I64d & %I64u

Description
Little Petya has recently started attending a programming club. Naturally he is facing the problem of choosing a programming language. After long considerations he realized that Java is the best choice. The main argument in favor of choosing Java was that it has a very large integer data type, called BigInteger.

But having attended several classes of the club, Petya realized that not all tasks require using the BigInteger type. It turned out that in some tasks it is much easier to use small data types. That's why a question arises: "Which integer type to use if one wants to store a positive integer n?"

Petya knows only 5 integer types:

1) byte occupies 1 byte and allows you to store numbers from  - 128 to 127

2) short occupies 2 bytes and allows you to store numbers from  - 32768 to 32767

3) int occupies 4 bytes and allows you to store numbers from  - 2147483648 to 2147483647

4) long occupies 8 bytes and allows you to store numbers from  - 9223372036854775808 to 9223372036854775807

5) BigInteger can store any integer number, but at that it is not a primitive type, and operations with it are much slower.

For all the types given above the boundary values are included in the value range.

From this list, Petya wants to choose the smallest type that can store a positive integer n. Since BigInteger works much slower, Peter regards it last. Help him.

Input
The first line contains a positive number n. It consists of no more than 100 digits and doesn't contain any leading zeros. The number ncan't be represented as an empty string.

Please, do not use %lld specificator to read or write 64-bit integers in C++. It is preffered to use cout (also you may use %I64d).

Output
Print the first type from the list "byte, short, int, long, BigInteger", that can store the natural number n, in accordance with the data given above.

Sample Input
Input
127
Output
byte
Input
130
Output
short
Input
123456789101112131415161718192021222324
Output
BigInteger

 

http://acm.hust.edu.cn/vjudge/contest/view.action?cid=122089#problem/B

主要是strcmp的使用

当s1<s2时，返回为负数；

当s1=s2时，返回值= 0；

当s1>s2时，返回正数。

即：两个字符串自左向右逐个字符相比（按ASCII值大小相比较），直到出现不同的字符或遇''为止。如："A"<"B" "a">"A" "computer">"compare"

特别注意：strcmp(const char *s1,const char * s2)这里面只能比较字符串，即可用于比较两个字符串常量，或比较数组和字符串常量，不能比较数字等其他形式的参数。

AC代码

#include <iostream>
#include <cstdio>
#include <queue>
#include <algorithm>
#include <string.h>
using namespace std;

char a[105];

int main()
{
    while(~scanf("%s",a))
    {
        int len=strlen(a);
        if(len<3||(len==3&&strcmp(a,"127")<=0))
            printf("byte
");
        else if(len<5||(len==5&&strcmp(a,"32767")<=0))
            printf("short
");
        else if(len<10||(len==10&&strcmp(a,"2147483647")<=0))
            printf("int
");
        else if(len<19||(len==19&&strcmp(a,"9223372036854775807")<=0))
            printf("long
");
        else
            printf("BigInteger
");
    }
}