2014-7-19

I did two questions yesterday, and I felt quite confused. But today I feel like remembering my efforts.

The first method is poj 3630 phone list.

A basic trie tree, but because of the dynamic build-up, it was just the beginning of TLE. Finally, the static storage method is used.

# Include <iostream> # include <cstdio> # include <cstring> using namespace STD; const int maxn = 100010; struct n {int next [11]; bool sign ;} node [maxn]; string s; int sum; bool add () {int Len = S. length (); int root = 0; For (INT I = 0; I <Len; I ++) {int TMP = s [I]-'0 '; if (node [root]. next [TMP]) {root = node [root]. next [TMP]; if (I = len-1) return 1; if (node [root]. sign) return 1;} else {node [root]. next [TMP] = sum; root = sum ++;} if (I = len-1) node [root]. sign = 1;} return 0;} int main () {int t; CIN> T; while (t --) {sum = 1; bool flag = 1; memset (node, 0, sizeof (node); int N; CIN> N; For (INT I = 0; I <n; I ++) {CIN> S; If (FLAG) if (add () Flag = 0;} If (FLAG) cout <"yes" <Endl; else cout <"no" <Endl ;}}



The second is poj 3067 Japan.

Is a tree array. It is also very simple, but it is also because of a very low-level mistake that caused Wa and TLE a few times.
During the final debugging, we found that the tree array was updated. If the input parameter is a negative number, it would be an endless loop. Then we suddenly realized that the negative number would eventually be 0, and then it would die.

#include <iostream>#include <cstdio>#include <algorithm>#include <vector>#include <cstring>using namespace std;const int maxn = 1010;struct N{    int f, l;} node[maxn * maxn];int sum[maxn];int n, m, k;vector<int> p;bool cmp(N a, N b){    return a.f > b.f;}void insert(int t){    while(t <= m)    {        sum[t] += 1;        t += t & (-t);    }}int findsum(int t){    t--;    int ret = 0;    while(t > 0)    {        ret += sum[t];        t -= t & (-t);    }    return ret;}void print(){    for(int i = 1; i <= m; i++)    cout << i << " " << sum[i] << endl;}int main(){    int t;    cin >> t;    for(int T = 0; T < t; T++)    {        memset(sum, 0, sizeof(sum));        cin >> n >> m >> k;        for(int i = 0; i < k; i++)            scanf("%d%d", &node[i].f, &node[i].l);        sort(node, node + k, cmp);        int tt = 0;        while(node[tt].f == node[0].f)        {            insert(node[tt].l);            tt++;        }        long long ans = 0;        for(int i = tt; i < k; i++)        {            if(node[i].f == node[i - 1].f)            {                ans += findsum(node[i].l);                p.push_back(node[i].l);            }            else            {                for(int j = 0; j < p.size(); j++)                    insert(p[j]);                p.clear();                ans += findsum(node[i].l);                p.push_back(node[i].l);            }        }        p.clear();        printf("Test case %d: %lld\n", T + 1, ans);    }}