大數比大小

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#include<iostream>
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#include<vector>
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using namespace std;
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int f(const vector<int>& a, const vector<int>& b) {
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    if (a.size() < b.size()) return -1;
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    if (a.size() > b.size()) return 1;
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    for (int i = a.size() - 1; i >= 0; i--) {
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        if (a[i] < b[i]) return -1;
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        if (a[i] > b[i]) return 1;
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    }
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    return 0;
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}
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int main(){
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    string a, b;
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    vector<int> a_int, b_int;
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    cin >> a >> b;
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    if (!a.empty()) {
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        for(int i = a.size() - 1; i >= 0; i--){
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            int digit = static_cast<int>(a[i]) - '0';
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            a_int.push_back(digit);
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        }
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    }
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    if (!b.empty()) {
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        for(int i = b.size() - 1; i >= 0; i--){
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            int digit = static_cast<int>(b[i]) - '0';
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            b_int.push_back(digit);
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        }
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    }
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    int cmp = f(a_int, b_int);
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    if (cmp == -1)
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        cout << "<" << endl;
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    else if (cmp == 1)
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        cout << ">" << endl;
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    else
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        cout << "=" << endl;
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}