18.12.21 【USACO】Times17

题目描述

After realizing that there is much money to be made in software development, Farmer John has launched a small side business writing short
programs for clients in the local farming industry. 

Farmer John's first programming task seems quite simple to him -- almost too simple: his client wants him to write a program that takes a number N as input, and prints 17 times N as output.  Farmer John has just finished writing this simple program when the client calls him up in a panic and informs him that the input and output both must be expressed as binary numbers, and that these might be quite large.

Please help Farmer John complete his programming task.  Given an input number N, written in binary with at most 1000 digits, please write out the binary representation of 17 times N.

输入

* Line 1: The binary representation of N (at most 1000 digits).

输出

* Line 1: The binary representation of N times 17.

样例输入

10110111

样例输出

110000100111

来源

USACO 2012 March Bronze

#include <iostream>
#include <string.h>
#include <algorithm>
#include <stack>
#include <string>
#include <math.h>
#include <queue>
#include <stdio.h>
#include <string.h>
#include <set>
#include <vector>
#include <fstream>
#define maxn 1005
#define inf 999999
#define cha 127
#define eps 1e-6 
#define oo 1503
using namespace std;

string a, b;
int n1[maxn], n2[maxn];

void init() {
    cin >> a;
    b = a + "0000";
    int sizea = a.length(), sizeb = b.length();
    for (int i = 4; i < sizeb; i++)
        n1[i] = a[i-4] - '0';
    for (int i = 0; i < sizeb; i++)
        n2[i] = b[i] - '0';
    for (int i = sizeb - 1; i >= 1; i--) {
        n2[i] = n2[i] + n1[i];
        n2[i - 1] += n2[i] / 2;
        n2[i] %= 2;
    }
    string tmp;
    while (n2[0] != 0) {
        char ch = n2[0] % 2 + '0';
        tmp = ch + tmp;
        n2[0] /= 2;
    }
    cout << tmp;
    for (int i = 1; i < sizeb; i++)
        printf("%d", n2[i]);
    printf("
");
}

int main() {
    init();
    return 0;
}