02-线性结构2 一元多项式的乘法与加法运算 （20 分)

#include<cstdio>
const int maxn = 2050;
int add[maxn] = {0};
int mul1[maxn] = {0},mul2[maxn];

int main(){
    int n;
    scanf("%d",&n);
    int exp,coe;      //exp指数，coe系数 
    for(int i = 0; i < n; i++){
        scanf("%d %d",&coe,&exp);
        add[exp] += coe;
        mul1[exp] += coe;
    }
    scanf("%d",&n);
    for(int i = 0; i < n; i++){
        scanf("%d %d",&coe,&exp);
        add[exp] += coe;
        for(int j = maxn; j >= 0; j--){
            if(mul1[j] != 0){
                mul2[j+exp] += mul1[j] * coe;
            }
        }
    }
    int cnt1 = 0,cnt2 = 0;
    for(int i = 0; i < maxn; i++){
        if(add[i] != 0) cnt1++;
        if(mul2[i] != 0) cnt2++;
    }
    if(cnt2 == 0) printf("0 0\n");
    else 
    for(int i = maxn; i >= 0; i--){
        if(mul2[i] != 0){
             printf("%d %d",mul2[i],i);
             cnt2--;
             if(cnt2 > 0) printf(" ");
             else printf("\n");
        }    
            
    }
    if(cnt1 == 0){
         printf("0 0");
         return 0;
    }
    for(int i = maxn; i >= 0; i--){
        if(add[i] != 0){
             printf("%d %d",add[i],i);
             cnt1--;
             if(cnt1 > 0) printf(" ");
             else printf("\n");
        }
    }
    return 0;
}