p0013_s0.py

problem 13 · 124 lines

#!/usr/bin/env python3.14
# -*- coding: utf-8 -*-
""" Solution to Euler Problem 13: Large Sum [Level 0]. """
from __future__ import annotations

from solver.runners import runner

numbers = (
    "37107287533902102798797998220837590246510135740250\n"
    "46376937677490009712648124896970078050417018260538\n"
    "74324986199524741059474233309513058123726617309629\n"
    "91942213363574161572522430563301811072406154908250\n"
    "23067588207539346171171980310421047513778063246676\n"
    "89261670696623633820136378418383684178734361726757\n"
    "28112879812849979408065481931592621691275889832738\n"
    "44274228917432520321923589422876796487670272189318\n"
    "47451445736001306439091167216856844588711603153276\n"
    "70386486105843025439939619828917593665686757934951\n"
    "62176457141856560629502157223196586755079324193331\n"
    "64906352462741904929101432445813822663347944758178\n"
    "92575867718337217661963751590579239728245598838407\n"
    "58203565325359399008402633568948830189458628227828\n"
    "80181199384826282014278194139940567587151170094390\n"
    "35398664372827112653829987240784473053190104293586\n"
    "86515506006295864861532075273371959191420517255829\n"
    "71693888707715466499115593487603532921714970056938\n"
    "54370070576826684624621495650076471787294438377604\n"
    "53282654108756828443191190634694037855217779295145\n"
    "36123272525000296071075082563815656710885258350721\n"
    "45876576172410976447339110607218265236877223636045\n"
    "17423706905851860660448207621209813287860733969412\n"
    "81142660418086830619328460811191061556940512689692\n"
    "51934325451728388641918047049293215058642563049483\n"
    "62467221648435076201727918039944693004732956340691\n"
    "15732444386908125794514089057706229429197107928209\n"
    "55037687525678773091862540744969844508330393682126\n"
    "18336384825330154686196124348767681297534375946515\n"
    "80386287592878490201521685554828717201219257766954\n"
    "78182833757993103614740356856449095527097864797581\n"
    "16726320100436897842553539920931837441497806860984\n"
    "48403098129077791799088218795327364475675590848030\n"
    "87086987551392711854517078544161852424320693150332\n"
    "59959406895756536782107074926966537676326235447210\n"
    "69793950679652694742597709739166693763042633987085\n"
    "41052684708299085211399427365734116182760315001271\n"
    "65378607361501080857009149939512557028198746004375\n"
    "35829035317434717326932123578154982629742552737307\n"
    "94953759765105305946966067683156574377167401875275\n"
    "88902802571733229619176668713819931811048770190271\n"
    "25267680276078003013678680992525463401061632866526\n"
    "36270218540497705585629946580636237993140746255962\n"
    "24074486908231174977792365466257246923322810917141\n"
    "91430288197103288597806669760892938638285025333403\n"
    "34413065578016127815921815005561868836468420090470\n"
    "23053081172816430487623791969842487255036638784583\n"
    "11487696932154902810424020138335124462181441773470\n"
    "63783299490636259666498587618221225225512486764533\n"
    "67720186971698544312419572409913959008952310058822\n"
    "95548255300263520781532296796249481641953868218774\n"
    "76085327132285723110424803456124867697064507995236\n"
    "37774242535411291684276865538926205024910326572967\n"
    "23701913275725675285653248258265463092207058596522\n"
    "29798860272258331913126375147341994889534765745501\n"
    "18495701454879288984856827726077713721403798879715\n"
    "38298203783031473527721580348144513491373226651381\n"
    "34829543829199918180278916522431027392251122869539\n"
    "40957953066405232632538044100059654939159879593635\n"
    "29746152185502371307642255121183693803580388584903\n"
    "41698116222072977186158236678424689157993532961922\n"
    "62467957194401269043877107275048102390895523597457\n"
    "23189706772547915061505504953922979530901129967519\n"
    "86188088225875314529584099251203829009407770775672\n"
    "11306739708304724483816533873502340845647058077308\n"
    "82959174767140363198008187129011875491310547126581\n"
    "97623331044818386269515456334926366572897563400500\n"
    "42846280183517070527831839425882145521227251250327\n"
    "55121603546981200581762165212827652751691296897789\n"
    "32238195734329339946437501907836945765883352399886\n"
    "75506164965184775180738168837861091527357929701337\n"
    "62177842752192623401942399639168044983993173312731\n"
    "32924185707147349566916674687634660915035914677504\n"
    "99518671430235219628894890102423325116913619626622\n"
    "73267460800591547471830798392868535206946944540724\n"
    "76841822524674417161514036427982273348055556214818\n"
    "97142617910342598647204516893989422179826088076852\n"
    "87783646182799346313767754307809363333018982642090\n"
    "10848802521674670883215120185883543223812876952786\n"
    "71329612474782464538636993009049310363619763878039\n"
    "62184073572399794223406235393808339651327408011116\n"
    "66627891981488087797941876876144230030984490851411\n"
    "60661826293682836764744779239180335110989069790714\n"
    "85786944089552990653640447425576083659976645795096\n"
    "66024396409905389607120198219976047599490197230297\n"
    "64913982680032973156037120041377903785566085089252\n"
    "16730939319872750275468906903707539413042652315011\n"
    "94809377245048795150954100921645863754710598436791\n"
    "78639167021187492431995700641917969777599028300699\n"
    "15368713711936614952811305876380278410754449733078\n"
    "40789923115535562561142322423255033685442488917353\n"
    "44889911501440648020369068063960672322193204149535\n"
    "41503128880339536053299340368006977710650566631954\n"
    "81234880673210146739058568557934581403627822703280\n"
    "82616570773948327592232845941706525094512325230608\n"
    "22918802058777319719839450180888072429661980811197\n"
    "77158542502016545090413245809786882778948721859617\n"
    "72107838435069186155435662884062257473692284509516\n"
    "20849603980134001723930671666823555245252804609722\n"
    "53503534226472524250874054075591789781264330331690\n"
)


@runner.main
def solve(*args: str) -> str:
    """Big-integer sum of the leading (digits+1) characters of each number, then keep the first
    `digits` characters; O(N·D) for N numbers of D digits. The one guard digit beyond the
    requested width absorbs carry from the discarded tail, so the leading `digits` places are exact."""
    digits = runner.parse_int(args[0])

    return str(str(sum([int(i[: digits + 1]) for i in numbers.splitlines() if i != ""]))[:digits])


if __name__ == "__main__":
    raise SystemExit(solve())