What are the steps to convert the base 2 signed binary number
0000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101(2) to a base 10 decimal system equivalent integer?
1. Is this a positive or a negative number?
0000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101 is the binary representation of a positive 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:
0000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101 = 000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101
3. Map the unsigned binary number's digits versus the corresponding powers of 2 that their place value represent:
262
0 261
0 260
0 259
0 258
0 257
0 256
0 255
0 254
0 253
0 252
0 251
1 250
1 249
1 248
1 247
0 246
1 245
0 244
1 243
1 242
1 241
0 240
1 239
1 238
0 237
1 236
0 235
0 234
1 233
0 232
0 231
0 230
0 229
1 228
0 227
0 226
1 225
0 224
1 223
1 222
1 221
0 220
1 219
0 218
1 217
1 216
0 215
0 214
0 213
1 212
1 211
1 210
1 29
1 28
0 27
1 26
0 25
1 24
0 23
0 22
1 21
0 20
1
4. Multiply each bit by its corresponding power of 2 and add all the terms up.
000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101(2) =
(0 × 262 + 0 × 261 + 0 × 260 + 0 × 259 + 0 × 258 + 0 × 257 + 0 × 256 + 0 × 255 + 0 × 254 + 0 × 253 + 0 × 252 + 1 × 251 + 1 × 250 + 1 × 249 + 1 × 248 + 0 × 247 + 1 × 246 + 0 × 245 + 1 × 244 + 1 × 243 + 1 × 242 + 0 × 241 + 1 × 240 + 1 × 239 + 0 × 238 + 1 × 237 + 0 × 236 + 0 × 235 + 1 × 234 + 0 × 233 + 0 × 232 + 0 × 231 + 0 × 230 + 1 × 229 + 0 × 228 + 0 × 227 + 1 × 226 + 0 × 225 + 1 × 224 + 1 × 223 + 1 × 222 + 0 × 221 + 1 × 220 + 0 × 219 + 1 × 218 + 1 × 217 + 0 × 216 + 0 × 215 + 0 × 214 + 1 × 213 + 1 × 212 + 1 × 211 + 1 × 210 + 1 × 29 + 0 × 28 + 1 × 27 + 0 × 26 + 1 × 25 + 0 × 24 + 0 × 23 + 1 × 22 + 0 × 21 + 1 × 20)(10) =
(0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 0 + 2 251 799 813 685 248 + 1 125 899 906 842 624 + 562 949 953 421 312 + 281 474 976 710 656 + 0 + 70 368 744 177 664 + 0 + 17 592 186 044 416 + 8 796 093 022 208 + 4 398 046 511 104 + 0 + 1 099 511 627 776 + 549 755 813 888 + 0 + 137 438 953 472 + 0 + 0 + 17 179 869 184 + 0 + 0 + 0 + 0 + 536 870 912 + 0 + 0 + 67 108 864 + 0 + 16 777 216 + 8 388 608 + 4 194 304 + 0 + 1 048 576 + 0 + 262 144 + 131 072 + 0 + 0 + 0 + 8 192 + 4 096 + 2 048 + 1 024 + 512 + 0 + 128 + 0 + 32 + 0 + 0 + 4 + 0 + 1)(10) =
(2 251 799 813 685 248 + 1 125 899 906 842 624 + 562 949 953 421 312 + 281 474 976 710 656 + 70 368 744 177 664 + 17 592 186 044 416 + 8 796 093 022 208 + 4 398 046 511 104 + 1 099 511 627 776 + 549 755 813 888 + 137 438 953 472 + 17 179 869 184 + 536 870 912 + 67 108 864 + 16 777 216 + 8 388 608 + 4 194 304 + 1 048 576 + 262 144 + 131 072 + 8 192 + 4 096 + 2 048 + 1 024 + 512 + 128 + 32 + 4 + 1)(10) =
4 325 084 241 477 285(10)
5. If needed, adjust the sign of the integer number by the first digit (leftmost) of the signed binary:
0000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101(2) = 4 325 084 241 477 285(10)
0000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101(2), Base 2 signed binary number, converted and written as a base 10 decimal system equivalent integer:
0000 0000 0000 1111 0101 1101 1010 0100 0010 0101 1101 0110 0011 1110 1010 0101(2) = 4 325 084 241 477 285(10)
Spaces were used to group digits: for binary, by 4, for decimal, by 3.