1 #include <cstdio>
2 #include <cstring>
3 using namespace std;
4 #define MAX 10005
5
6 struct bigint
7 {
8 char num[MAX];
9 int flag; // 1:positive -1:negative
10 int dgts;
11 bigint(void)
12 {
13 memset(num, '0', sizeof(num));
14 }
15 };
16
17 void BigIntTrans(char str[], bigint* a) //convert string to the structure of bigint
18 {
19 int i, k, len;
20 len = strlen(str);
21 a->flag = 1;
22 a->dgts = len;
23 k = 0;
24 for(i = len - 1; i >= 1; --i)
25 a->num[k++] = str[i];
26 if(str[0] == '-') {
27 a->flag = -1;
28 --a->dgts;
29 }
30 else {
31 a->num[k++] = str[i];
32 }
33 }
34
35 void BigIntPrint(bigint* a)
36 {
37 int i;
38 if(a->flag == -1) printf("-");
39 if(a->dgts == 1 && a->num[0] == '0') {
40 printf("0\n");
41 return;
42 }
43 i = a->dgts - 1;
44 while(a->num[i] == '0')
45 --i;
46 for( ; i >= 0; --i) {
47 printf("%c", a->num[i]);
48 }
49 printf("\n");
50 }
51
52 void add(bigint* a, bigint* b, bigint* ans)
53 {
54 int i, c=0, len, tmp;
55 len = (a->dgts >= b->dgts? a->dgts:b->dgts);
56 for(i = 0; i < len; ++i) {
57 tmp = (a->num[i]-'0') + (b->num[i]-'0') + c;
58 if(tmp >= 10){
59 c = 1;
60 ans->num[i] = (tmp % 10) + '0';
61 }
62 else {
63 c = 0;
64 ans->num[i] = tmp + '0';
65 }
66 }
67 if(c) {
68 ans->num[i] = '1';
69 ans->dgts = len + 1;
70 }
71 else ans->dgts = len;
72 if(a->flag + b->flag == 2) ans->flag = 1;
73 else ans->flag = -1;
74 }
75
76 void sub(bigint* a, bigint* b, bigint* ans)
77 {
78 int i, c=0, tmp;
79 for(i = 0; i < a->dgts; ++i) {
80 tmp = (a->num[i]-'0') - (b->num[i]-'0') - c;
81 if(tmp >= 0) {
82 ans->num[i] = tmp + '0';
83 c = 0;
84 }
85 else {
86 ans->num[i] = tmp + 10 + '0';
87 c = 1;
88 }
89 }
90 ans->dgts = a->dgts;
91 ans->flag = a->flag;
92 }
93
94 int cmpabs(bigint* a, bigint* b)
95 {
96 if(a->dgts > b->dgts)
97 return 1;
98 else if(a->dgts < b->dgts)
99 return 2;
100 else {
101 for(int i = a->dgts - 1; i >= 0; --i) {
102 if(a->num[i] > b->num[i]) return 1;
103 else if(a->num[i] < b->num[i]) return 2;
104 else continue;
105 }
106 return 0;
107 }
108 }
109
110 void BigIntAdd(bigint* a, bigint* b, bigint* ans)
111 {
112 int flag;
113 if(a->flag * b->flag == 1)
114 add(a, b, ans);
115 else if(a->flag * b->flag == -1) {
116 flag = cmpabs(a, b);
117 if(flag == 1) sub(a, b, ans);
118 else if(flag == 2) sub(b, a, ans);
119 else {
120 ans->dgts = 1;
121 ans->num[0] = '0';
122 ans->flag = 1;
123 }
124 }
125
126 }
127
128 char str1[MAX], str2[MAX];
129
130 int main()
131 {
132 bigint a, b, ans;
133 scanf("%s%s", str1, str2);
134 BigIntTrans(str1, &a);
135 BigIntTrans(str2, &b);
136 sub(&a, &b, &ans);
137 BigIntPrint(&ans);
138 BigIntAdd(&a, &b, &ans);
139 BigIntPrint(&ans);
140 return 0;
141 }
