String Manipulation

by black strings

JavaScript

var str = `1980050 1983872 1983918 1983972 1986066 1986094 1986116 1986137 1986158 1986181 1986201 1986220 1986238 1986263 1986288 1986389 1986441 1989004 1989199 1989242 1989296 1989311 
1980051 1983880 1983919 1983991 1986068 1986096 1986118 1986139 1986160 1986183 1986202 1986221 1986240 1986265 1986290 1986390 1986442 1989006 1989205 1989246 1989297 1989312 
1980052 1983881 1983920 1986031 1986069 1986097 1986119 1986140 1986161 1986185 1986203 1986222 1986241 1986266 1986291 1986391 1986500 1989011 1989206 1989247 1989298 1989313 
1980053 1983882 1983930 1986032 1986071 1986098 1986120 1986141 1986162 1986186 1986205 1986223 1986242 1986268 1986293 1986400 1986501 1989016 1989207 1989248 1989299 1989314 
1982010 1983890 1983931 1986033 1986080 1986100 1986122 1986143 1986164 1986187 1986206 1986225 1986243 1986270 1986296 1986401 1986502 1989020 1989208 1989249 1989300 1989324 
1982011 1983900 1983932 1986051 1986081 1986101 1986123 1986145 1986166 1986188 1986207 1986226 1986245 1986271 1986297 1986402 1986505 1989021 1989230 1989255 1989301 1989325 
1982013 1983901 1983936 1986052 1986082 1986102 1986124 1986146 1986167 1986190 1986208 1986227 1986246 1986273 1986298 1986405 1986506 1989022 1989231 1989256 1989302 1989326 
1982025 1983902 1983937 1986058 1986084 1986104 1986126 1986148 1986169 1986191 1986210 1986228 1986247 1986275 1986351 1986406 1986507 1989026 1989232 1989280 1989303 1989328 
1982026 1983906 1983938 1986059 1986085 1986106 1986128 1986149 1986170 1986192 1986211 1986230 1986248 1986276 1986352 1986407 1986510 1989028 1989233 1989281 1989304 1989329 
1982028 1983907 1983942 1986060 1986086 1986107 1986129 1986150 1986171 1986193 1986212 1986231 1986250 1986278 1986353 1986410 1986511 1989030 1989234 1989290 1989305 1989330 
1982051 1983908 1983943 1986061 1986088 1986109 1986131 1986152 1986173 1986195 1986213 1986232 1986251 1986280 1986354 1986411 1986512 1989031 1989237 1989291 1989306 1989332 
1982052 1983912 1983944 1986062 1986089...