【洛谷-P1200】解题报告（字符串）

原始题目

P1200 [USACO1.1]你的飞碟在这儿

题目大意

字母'A'~'Z'对应1到26，字符串hash为对应值相乘mod47，若两字符串相等则输出"GO",否则"STAY".

解题思路

字符串hash

解题代码

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#include <bits/stdc++.h>
#include <sstream>
using namespace std;
typedef long long ll;
typedef unsigned long long ull;
typedef vector<int> vi;
typedef pair<int, int> pii;
typedef pair<string, string> pss;

#define rep(i, a, n) for (int i = a; i < n; ++i)
#define per(i, a, n) for (int i = n - 1; i >= a; --i)
#define fi first
#define se second
#define pb push_back
#define mp make_pair
#define np next_permutation
#define INF 0x3f3f3f3f
#define EPS 1e-8
#define endl '\n'
string a, b;
const int mod = 47;
const int maxn = 1e5 + 5;

int main()
{
    ios::sync_with_stdio(false);
    while (cin >> a >> b) {
        int ans = 1, ans2 = 1;
        rep(i, 0, a.length())
        {
            ans = (ans * (a[i] - 'A' + 1)) % mod;
        }
        rep(i, 0, b.length())
        {
            ans2 = (ans2 * (b[i] - 'A' + 1)) % mod;
        }
        if (ans == ans2)
            cout << "GO" << endl;
        else
            cout << "STAY" << endl;
    }
}

收获与反思

字符串hash入门