【A + B + C + D】 問題

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A + B + C + D

Time Limit: 40000/20000 MS (Java/Others)    Memory Limit: 32768/32768 K (Java/Others)
Total Submission(s): 130    Accepted Submission(s): 44

Problem DescriptionLittle Robert asked his mother for two cents. "What did you do withthe money I gave you yesterday?""I gave it to a poor old woman," heanswered."You‘re a good boy," said the mother proudly. "Here aretwo cents more. But why are you so interested in the oldwoman?""She is the one who sells the candy."A joke, hereentered
Below n four tuple (A, B, C, D), respectively, from the A, B, C, Dselected a, b ,c ,d To calculate the number of combinations ofa+b+c+d = 0; 

 

InputThe first line of the input file contains the size of the lists n(1<= n <= 4000)
Then every line containing four integer values (with absolute valueas large as 2^28 ) OutputFor each input file, your program has to write the number whose sumis zero 

 

Sample Input6 -45 22 42 -16 -41 -27 56 30 -36 53 -37 77 -36 30 -75 -46 26 -38-10 62 -32 -54 -6 45 Sample Output5   

#include <cstdio>#include <iostream>#include <algorithm>using namespace std;const int maxn=4010;int n;int s1[maxn*maxn];int s2[maxn*maxn];int a[maxn],b[maxn],c[maxn],d[maxn];int main(){//   freopen("in.txt", "r", stdin);    while(~scanf("%d", &n))    {for (int i=0;i<n;i++)        scanf("%d%d%d%d",&a[i],&b[i],&c[i],&d[i]);    for (int i=0;i<n;i++)        for (int j=0;j<n;j++)            s1[i*n+j]=a[i]+b[j];    for (int i=0;i<n;i++)        for (int j=0;j<n;j++)            s2[i*n+j] = c[i]+d[j];    sort(s1,s1+n*n);    sort(s2,s2+n*n);    int r = n*n-1;    int ans =0;    for (int i=0;i<n*n;i++)    {        while(r>=0 && s1[i]+s2[r]>0)            r--;        if (r < 0)break;        int tmp = r;        while (tmp >= 0 && s1[i]+s2[tmp] == 0)            ans++, tmp--;    }    printf("%d\n", ans);    }    return 0;}

 

【A + B + C + D】 問題