Description
standard input/output
Statements
Statements
You are given three numbers. Is there a way to replace variables A, B and C with these numbers so the equality A + B = C is correct?
Input
There are three numbers X1, X2 and X3 (1 ≤ Xi ≤ 10100), each on a separate line of input.
Output
Output either "YES", if there is a way to substitute variables A, B and C with given numbers so the equality is correct, or "NO" otherwise.
Sample Input
Input
1
2
3
Output
YES
Input
1
2
4
Output
YES
Input
1
3
5
Output
NO
题意： 给你3 个数，让你判断其中任意两个数的和是否可以组成这三个树种的一个，这些数都可以重复使用。
分析： 高精度
1 #include<string> 2 #include<iostream> 3 #include<iosfwd> 4 #include<cmath> 5 #include<cstring> 6 #include<stdlib.h> 7 #include<stdio.h> 8 #include<cstring> 9 #define MAX_L 2005 //最大长度，可以修改 10 using namespace std; 11 12 class bign 13 { 14 public: 15 int len, s[MAX_L];//数的长度，记录数组 16 //构造函数 17 bign(); 18 bign(const char*); 19 bign(int); 20 bool sign;//符号 1正数 0负数 21 string toStr() const;//转化为字符串，主要是便于输出 22 friend istream& operator>>(istream &,bign &);//重载输入流 23 friend ostream& operator<<(ostream &,bign &);//重载输出流 24 //重载复制 25 bign operator=(const char*); 26 bign operator=(int); 27 bign operator=(const string); 28 //重载各种比较 29 bool operator>(const bign &) const; 30 bool operator>=(const bign &) const; 31 bool operator<(const bign &) const; 32 bool operator<=(const bign &) const; 33 bool operator==(const bign &) const; 34 bool operator!=(const bign &) const; 35 //重载四则运算 36 bign operator+(const bign &) const; 37 bign operator++(); 38 bign operator++(int); 39 bign operator+=(const bign&); 40 bign operator-(const bign &) const; 41 bign operator--(); 42 bign operator--(int); 43 bign operator-=(const bign&); 44 bign operator*(const bign &)const; 45 bign operator*(const int num)const; 46 bign operator*=(const bign&); 47 bign operator/(const bign&)const; 48 bign operator/=(const bign&); 49 //四则运算的衍生运算 50 bign operator%(const bign&)const;//取模（余数） 51 bign factorial()const;//阶乘 52 bign Sqrt()const;//整数开根（向下取整） 53 bign pow(const bign&)const;//次方 54 //一些乱乱的函数 55 void clean(); 56 ~bign(); 57 }; 58 #define max(a,b) a>b ? a : b 59 #define min(a,b) a<b ? a : b 60 61 bign::bign() 62 { 63 memset(s, 0, sizeof(s)); 64 len = 1; 65 sign = 1; 66 } 67 68 bign::bign(const char *num) 69 { 70 *this = num; 71 } 72 73 bign::bign(int num) 74 { 75 *this = num; 76 } 77 78 string bign::toStr() const 79 { 80 string res; 81 res = ""; 82 for (int i = 0; i < len; i++) 83 res = (char)(s[i] + '0') + res; 84 if (res == "") 85 res = "0"; 86 if (!sign&&res != "0") 87 res = "-" + res; 88 return res; 89 } 90 91 istream &operator>>(istream &in, bign &num) 92 { 93 string str; 94 in>>str; 95 num=str; 96 return in; 97 } 98 99 ostream &operator<<(ostream &out, bign &num) 100 { 101 out<<num.toStr(); 102 return out; 103 } 104 105 bign bign::operator=(const char *num) 106 { 107 memset(s, 0, sizeof(s)); 108 char a[MAX_L] = ""; 109 if (num[0] != '-') 110 strcpy(a, num); 111 else 112 for (int i = 1; i < strlen(num); i++) 113 a[i - 1] = num[i]; 114 sign = !(num[0] == '-'); 115 len = strlen(a); 116 for (int i = 0; i < strlen(a); i++) 117 s[i] = a[len - i - 1] - 48; 118 return *this; 119 } 120 121 bign bign::operator=(int num) 122 { 123 char temp[MAX_L]; 124 sprintf(temp, "%d", num); 125 *this = temp; 126 return *this; 127 } 128 129 bign bign::operator=(const string num) 130 { 131 const char *tmp; 132 tmp = num.c_str(); 133 *this = tmp; 134 return *this; 135 } 136 137 bool bign::operator<(const bign &num) const 138 { 139 if (sign^num.sign) 140 return num.sign; 141 if (len != num.len) 142 return len < num.len; 143 for (int i = len - 1; i >= 0; i--) 144 if (s[i] != num.s[i]) 145 return sign ? (s[i] < num.s[i]) : (!(s[i] < num.s[i])); 146 return !sign; 147 } 148 149 bool bign::operator>(const bign&num)const 150 { 151 return num < *this; 152 } 153 154 bool bign::operator<=(const bign&num)const 155 { 156 return !(*this>num); 157 } 158 159 bool bign::operator>=(const bign&num)const 160 { 161 return !(*this<num); 162 } 163 164 bool bign::operator!=(const bign&num)const 165 { 166 return *this > num || *this < num; 167 } 168 169 bool bign::operator==(const bign&num)const 170 { 171 return !(num != *this); 172 } 173 174 bign bign::operator+(const bign &num) const 175 { 176 if (sign^num.sign) 177 { 178 bign tmp = sign ? num : *this; 179 tmp.sign = 1; 180 return sign ? *this - tmp : num - tmp; 181 } 182 bign result; 183 result.len = 0; 184 int temp = 0; 185 for (int i = 0; temp || i < (max(len, num.len)); i++) 186 { 187 int t = s[i] + num.s[i] + temp; 188 result.s[result.len++] = t % 10; 189 temp = t / 10; 190 } 191 result.sign = sign; 192 return result; 193 } 194 195 bign bign::operator++() 196 { 197 *this = *this + 1; 198 return *this; 199 } 200 201 bign bign::operator++(int) 202 { 203 bign old = *this; 204 ++(*this); 205 return old; 206 } 207 208 bign bign::operator+=(const bign &num) 209 { 210 *this = *this + num; 211 return *this; 212 } 213 214 bign bign::operator-(const bign &num) const 215 { 216 bign b=num,a=*this; 217 if (!num.sign && !sign) 218 { 219 b.sign=1; 220 a.sign=1; 221 return b-a; 222 } 223 if (!b.sign) 224 { 225 b.sign=1; 226 return a+b; 227 } 228 if (!a.sign) 229 { 230 a.sign=1; 231 b=bign(0)-(a+b); 232 return b; 233 } 234 if (a<b) 235 { 236 bign c=(b-a); 237 c.sign=false; 238 return c; 239 } 240 bign result; 241 result.len = 0; 242 for (int i = 0, g = 0; i < a.len; i++) 243 { 244 int x = a.s[i] - g; 245 if (i < b.len) x -= b.s[i]; 246 if (x >= 0) g = 0; 247 else 248 { 249 g = 1; 250 x += 10; 251 } 252 result.s[result.len++] = x; 253 } 254 result.clean(); 255 return result; 256 } 257 258 bign bign::operator * (const bign &num)const 259 { 260 bign result; 261 result.len = len + num.len; 262 263 for (int i = 0; i < len; i++) 264 for (int j = 0; j < num.len; j++) 265 result.s[i + j] += s[i] * num.s[j]; 266 267 for (int i = 0; i < result.len; i++) 268 { 269 result.s[i + 1] += result.s[i] / 10; 270 result.s[i] %= 10; 271 } 272 result.clean(); 273 result.sign = !(sign^num.sign); 274 return result; 275 } 276 277 bign bign::operator*(const int num)const 278 { 279 bign x = num; 280 bign z = *this; 281 return x*z; 282 } 283 bign bign::operator*=(const bign&num) 284 { 285 *this = *this * num; 286 return *this; 287 } 288 289 bign bign::operator /(const bign&num)const 290 { 291 bign ans; 292 ans.len = len - num.len + 1; 293 if (ans.len < 0) 294 { 295 ans.len = 1; 296 return ans; 297 } 298 299 bign divisor = *this, divid = num; 300 divisor.sign = divid.sign = 1; 301 int k = ans.len - 1; 302 int j = len - 1; 303 while (k >= 0) 304 { 305 while (divisor.s[j] == 0) j--; 306 if (k > j) k = j; 307 char z[MAX_L]; 308 memset(z, 0, sizeof(z)); 309 for (int i = j; i >= k; i--) 310 z[j - i] = divisor.s[i] + '0'; 311 bign dividend = z; 312 if (dividend < divid) { k--; continue; } 313 int key = 0; 314 while (divid*key <= dividend) key++; 315 key--; 316 ans.s[k] = key; 317 bign temp = divid*key; 318 for (int i = 0; i < k; i++) 319 temp = temp * 10; 320 divisor = divisor - temp; 321 k--; 322 } 323 ans.clean(); 324 ans.sign = !(sign^num.sign); 325 return ans; 326 } 327 328 bign bign::operator/=(const bign&num) 329 { 330 *this = *this / num; 331 return *this; 332 } 333 334 bign bign::operator%(const bign& num)const 335 { 336 bign a = *this, b = num; 337 a.sign = b.sign = 1; 338 bign result, temp = a / b*b; 339 result = a - temp; 340 result.sign = sign; 341 return result; 342 } 343 344 bign bign::pow(const bign& num)const 345 { 346 bign result = 1; 347 for (bign i = 0; i < num; i++) 348 result = result*(*this); 349 return result; 350 } 351 352 bign bign::factorial()const 353 { 354 bign result = 1; 355 for (bign i = 1; i <= *this; i++) 356 result *= i; 357 return result; 358 } 359 360 void bign::clean() 361 { 362 if (len == 0) len++; 363 while (len > 1 && s[len - 1] == ' ') 364 len--; 365 } 366 367 bign bign::Sqrt()const 368 { 369 if(*this<0)return -1; 370 if(*this<=1)return *this; 371 bign l=0,r=*this,mid; 372 while(r-l>1) 373 { 374 mid=(l+r)/2; 375 if(mid*mid>*this) 376 r=mid; 377 else 378 l=mid; 379 } 380 return l; 381 } 382 383 bign::~bign() 384 { 385 } 386 387 bign a,b,c; 388 389 int main() 390 { 391 cin >> a >> b >> c; 392 bool flag = false; 393 if(a + b == c) flag = true; 394 if(a + c == b) flag = true; 395 if(a + a == b) flag = true; 396 if(a + a == c) flag = true; 397 if(b + b == a) flag = true; 398 if(b + b == c) flag = true; 399 if(b + c == a) flag = true; 400 if(c + c == a) flag = true; 401 if(c + c == b) flag = true; 402 if(flag) cout << "YES" << endl; 403 else cout << "NO" << endl; 404 return 0; 405 }