What are the steps to convert the base 2 signed binary number
1110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000(2) to a base 10 decimal system equivalent integer?
1. Is this a positive or a negative number?
1110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000 is the binary representation of a negative integer, on 64 bits (8 Bytes).
- In a signed binary, the first bit (the leftmost) is reserved for the sign, 1 = negative, 0 = positive. This bit does not count when calculating the absolute value.
2. Construct the unsigned binary number.
Exclude the first bit (the leftmost), that is reserved for the sign:
1110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000 = 110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000
3. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:
262
1 261
1 260
0 259
1 258
0 257
1 256
1 255
1 254
1 253
1 252
1 251
0 250
0 249
1 248
0 247
0 246
1 245
0 244
0 243
0 242
0 241
0 240
0 239
0 238
0 237
0 236
0 235
1 234
0 233
1 232
0 231
0 230
0 229
0 228
1 227
1 226
0 225
0 224
0 223
0 222
1 221
0 220
0 219
0 218
0 217
0 216
0 215
0 214
1 213
1 212
1 211
0 210
1 29
0 28
1 27
1 26
1 25
0 24
1 23
0 22
0 21
0 20
0
4. Multiply each bit by its corresponding power of 2 and add all the terms up.
110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000(2) =
(1 × 262 + 1 × 261 + 0 × 260 + 1 × 259 + 0 × 258 + 1 × 257 + 1 × 256 + 1 × 255 + 1 × 254 + 1 × 253 + 1 × 252 + 0 × 251 + 0 × 250 + 1 × 249 + 0 × 248 + 0 × 247 + 1 × 246 + 0 × 245 + 0 × 244 + 0 × 243 + 0 × 242 + 0 × 241 + 0 × 240 + 0 × 239 + 0 × 238 + 0 × 237 + 0 × 236 + 1 × 235 + 0 × 234 + 1 × 233 + 0 × 232 + 0 × 231 + 0 × 230 + 0 × 229 + 1 × 228 + 1 × 227 + 0 × 226 + 0 × 225 + 0 × 224 + 0 × 223 + 1 × 222 + 0 × 221 + 0 × 220 + 0 × 219 + 0 × 218 + 0 × 217 + 0 × 216 + 0 × 215 + 1 × 214 + 1 × 213 + 1 × 212 + 0 × 211 + 1 × 210 + 0 × 29 + 1 × 28 + 1 × 27 + 1 × 26 + 0 × 25 + 1 × 24 + 0 × 23 + 0 × 22 + 0 × 21 + 0 × 20)(10) =
(4 611 686 018 427 387 904 + 2 305 843 009 213 693 952 + 0 + 576 460 752 303 423 488 + 0 + 144 115 188 075 855 872 + 72 057 594 037 927 936 + 36 028 797 018 963 968 + 18 014 398 509 481 984 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 0 + 0 + 562 949 953 421 312 + 0 + 0 + 70 368 744 177 664 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 34 359 738 368 + 0 + 8 589 934 592 + 0 + 0 + 0 + 0 + 268 435 456 + 134 217 728 + 0 + 0 + 0 + 0 + 4 194 304 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 16 384 + 8 192 + 4 096 + 0 + 1 024 + 0 + 256 + 128 + 64 + 0 + 16 + 0 + 0 + 0 + 0)(10) =
(4 611 686 018 427 387 904 + 2 305 843 009 213 693 952 + 576 460 752 303 423 488 + 144 115 188 075 855 872 + 72 057 594 037 927 936 + 36 028 797 018 963 968 + 18 014 398 509 481 984 + 9 007 199 254 740 992 + 4 503 599 627 370 496 + 562 949 953 421 312 + 70 368 744 177 664 + 34 359 738 368 + 8 589 934 592 + 268 435 456 + 134 217 728 + 4 194 304 + 16 384 + 8 192 + 4 096 + 1 024 + 256 + 128 + 64 + 16)(10) =
7 778 349 918 522 996 176(10)
5. If needed, adjust the sign of the integer number by the first digit (leftmost) of the signed binary:
1110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000(2) = -7 778 349 918 522 996 176(10)
1110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000(2), Base 2 signed binary number, converted and written as a base 10 decimal system equivalent integer:
1110 1011 1111 0010 0100 0000 0000 1010 0001 1000 0100 0000 0111 0101 1101 0000(2) = -7 778 349 918 522 996 176(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.