PAT 甲级 1002 A+B for polynomials

利用hash表的思想

#include<iostream>

#include<vector>

 

using namespace std;

 

typedef struct {

    int exp;

    double coef;

}node;

 

node a[11], b[11];

 

int main() {

    int ka, i, kb, count = 0, k = 0;

    double data[1001] = { 0 };

    cin >> ka;

    for (i = 0; i < ka; i++) {

        cin >> a[i].exp >> a[i].coef;

        data[a[i].exp] += a[i].coef;

    }

    cin >> kb;

    for (i = 0; i < kb; i++) {

        cin >> b[i].exp >> b[i].coef;

        data[b[i].exp] += b[i].coef;

    }

    for (i = 0; i < 1001; i++) {

        if (data[i])

            count++;

    }

    cout << count;

for (i = 1000; i >= 0 && k < count; i--) {

        if (data[i]) {

            k++;

            printf(" %d %.1lf", i, data[i]);

        }

        

    }

    return 0;

}