hihocoder 1198 Memory Allocating Algorithm

 1 #include <stdio.h>
 2 #include <stdlib.h>
 3 #include <iostream>
 4 #include <string.h>
 5 #include <limits.h>
 6 #include <queue>
 7 #include <vector>
 8 #include <set>
 9 #include <map>
10 #include <algorithm>
11 #define LL long long
12 
13 using namespace std;
14 int N;
15 LL M;
16 vector<pair<LL, LL> > blank;
17 queue<pair<LL, LL> > usemem;
18 int cur = 1;
19 
20 int find_blank(LL len) {
21     LL min_len = M;
22     int min_index = -1;
23     for (int i=0;i<blank.size();++i) {
24         if(blank[i].second-blank[i].first >= len) {
25             min_len = blank[i].second-blank[i].first;
26             min_index = i;
27         }
28     }
29     return min_index;
30 }
31 
32 void insert_usemem(int i, LL len) {
33     usemem.push(make_pair(blank[i].first, blank[i].first+len));
34     blank[i].first += len;
35 }
36 
37 void erase_usemem() {
38     pair<LL, LL> p = usemem.front();
39     int left = -1, right = -1;
40     for (int i=0;i<blank.size();++i) {
41         if (blank[i].second == p.first) {
42             left = i;
43         } else if (blank[i].first == p.second) {
44             right = i;
45         }
46     }
47     if (left>=0 && right<0) {
48         blank[left].second = p.second;
49     } else if (left<=0 && right>=0) {
50         blank[right].first = p.first;
51     } else if (left>=0 && right >=0) {
52         blank[left].second = blank[right].second;
53         blank.erase(blank.begin()+right);
54     } else {
55         blank.push_back(make_pair(p.first, p.second));
56     }
57     usemem.pop();
58     cur++;
59 }
60 
61 int go(LL len) {
62     int index = find_blank(len);
63     //printf("need mem [%d], result [%d]...\n", int(len), index);
64     if (index < 0) {
65         erase_usemem();
66         return -1;
67     } else {
68         insert_usemem(index, len);
69         //printf("insert in pos [%d]...\n", int(blank[index].first-len));
70     }
71     return 0;
72 }
73 
74 
75 int main()
76 {
77     scanf("%d%lld", &N, &M);
78     blank.push_back(make_pair(0, M));
79     for (int i=0;i<N;++i) {
80         LL len;
81         scanf("%lld", &len);
82         while(1) {
83             if (go(len) == 0) break;
84         }
85     }
86     while(!usemem.empty()) {
87         pair<LL, LL> p = usemem.front();
88         printf("%d %lld\n", cur++, p.first);
89         usemem.pop();
90     }
91     return 0;
92 }