基准时间限制：1 秒 空间限制：131072 KB
给出2个大整数A,B，计算A+B的结果。
Input
第1行：大数A 第2行：大数B (A,B的长度 <= 10000 需注意：A B有可能为负数）
Output
输出A + B
Input示例
68932147586 468711654886
Output示例
537643802472
1 #include <stdio.h> 2 #include <stdlib.h> 3 #include <string.h> 4 5 char A[10005]; 6 char B[10005]; 7 int fa, fb; 8 9 void swap(char* a, int i, int j) 10 { 11 char t = a[i] - '0'; 12 a[i] = a[j] - '0'; 13 a[j] = t; 14 } 15 16 void add(char* a, char* b) 17 { 18 int la, lb, i, j, s, l, c=0; 19 la = strlen(a); 20 lb = strlen(b); 21 22 for (i = fa, j = la-1; i <= j; ++i, --j) swap(a, i, j); 23 for (i = fb, j = lb-1; i <= j; ++i, --j) swap(b, i, j); 24 25 for (i = fa; i<la || i<lb; ++i) { 26 s = a[i] + b[i] + c; 27 c = s / 10; 28 a[i] = s % 10; 29 } 30 a[i] = c; 31 l = c ? i : i-1; 32 if (fa) printf("-"); 33 for (i = l; i >= fa; --i) printf("%d", a[i]); 34 } 35 36 int cmp(char* a, char* b) 37 { 38 int i; 39 int la = strlen(a); 40 int lb = strlen(b); 41 42 if (la-fa > lb-fb) 43 return 1; 44 else if (la-fa < lb-fb) 45 return 0; 46 else { 47 for (i = 0; i < la && a[i+fa]==b[i+fb]; ++i); 48 return a[i+fa] > b[i+fb]; 49 } 50 } 51 52 void minus(char* a, char* b) 53 { 54 char* tmp; 55 int la, lb, i, j, s, l, t, c=0; 56 57 if (!cmp(a, b)) { 58 tmp = a; a = b; b = tmp; 59 t = fa; fa = fb; fb = t; 60 } 61 la = strlen(a); 62 lb = strlen(b); 63 for (i = fa, j = la-1; i <= j; ++i, --j) swap(a, i, j); 64 for (i = fb, j = lb-1; i <= j; ++i, --j) swap(b, i, j); 65 l = -1; 66 for (i = 0; i+fa < la; ++i) { 67 s = a[i+fa] - b[i+fb] - c >= 0 ? 0 : 1; 68 a[i+fa] = (a[i+fa] - b[i+fb] - c + 10) % 10; 69 l = a[i+fa] ? i+fa : l; 70 c = s; 71 } 72 if (l < 0) printf("0"); 73 else { 74 if (fa) printf("-"); 75 for (i = l; i >= fa; --i) printf("%d", a[i]); 76 } 77 } 78 79 int main () 80 { 81 scanf("%s%s", A, B); 82 fa = ('-' == A[0]); 83 fb = ('-' == B[0]); 84 if (fa^fb) 85 minus(A, B); 86 else 87 add(A, B); 88 return 0; 89 }