“浮点数的比较”

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#include <iostream>
#include <cstdio>
#include <cmath>

using namespace std;

int main(){
    float a;
    float b;
    float limit;
    cin >> a;
    cin >> b;
    cin >> limit;
    if (fabs(a - b) < limit){
        cout << "=" << endl;
    }else if(a > b){
        cout << ">" << endl;
    }else cout << "<" << endl;
    return 0;
}

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#include <iostream>
#include <cstdio>
#include <cmath>
#include <string>
#include <cstdlib>

using namespace std;

bool exchanged = false;

void exchange(string *a, string *b){
    if (a->length() > b->length()){
        string temp;
        temp = *a;
        *a = *b;
        *b = temp;
        exchanged = true;
    }
}

void _cout(char c){
    if (!exchanged){
        cout << c << endl;
    }else if (c == '>'){
        cout << '<' << endl;
    }else cout << '>' << endl;
}

int main(){
    string a,b;
    cin >> a;
    cin >> b;
    exchange(&a, &b);
    if (a[0] == '-' && b[0] != '-') {
        _cout('<');
        exit(0);
    }
    if (a[0] != '-' && b[0] == '-') {
        _cout('>');
        exit(0);
    }
    int begin = 0;
    int len = (int)a.length();
    int end = (int)b.length();
    if (a[0] == '-') begin = 1;
    for (int i = begin; i < len; i++){
        if (a[i] == '.' && b[i] != '.'){
            _cout('<');
            exit(0);
        }
        if (a[i] != '.' && b[i] == '.'){
            _cout('>');
            exit(0);
        }
        if (a[i] == b[i]){
            continue;
        }else if(a[i] > b[i]){
            _cout('>');
            exit(0);
        }else {
            _cout('<');
            exit(0);
        }
    }
    for (int i = len; i < end; i++){
        if (b[i] != '0') {
            _cout('<');
            exit(0);
            
        }
    }
    cout << "=" << endl;
    return 0;
}