PhoenixWright

#include <iostream>
#include <stdio.h>
#include <string.h>
#include <math.h>
 
using namespace std;
const char str[] =
    "73167176531330624919225119674426574742355349194934"
    "96983520312774506326239578318016984801869478851843"
    "85861560789112949495459501737958331952853208805511"
    "12540698747158523863050715693290963295227443043557"
    "66896648950445244523161731856403098711121722383113"
    "62229893423380308135336276614282806444486645238749"
    "30358907296290491560440772390713810515859307960866"
    "70172427121883998797908792274921901699720888093776"
    "65727333001053367881220235421809751254540594752243"
    "52584907711670556013604839586446706324415722155397"
    "53697817977846174064955149290862569321978468622482"
    "83972241375657056057490261407972968652414535100474"
    "82166370484403199890008895243450658541227588666881"
    "16427171479924442928230863465674813919123162824586"
    "17866458359124566529476545682848912883142607690042"
    "24219022671055626321111109370544217506941658960408"
    "07198403850962455444362981230987879927244284909188"
    "84580156166097919133875499200524063689912560717606"
    "05886116467109405077541002256983155200055935729725"
    "71636269561882670428252483600823257530420752963450";
int main() {
    int l = strlen(str);
    int sum = (str[0]-'0') * (str[1]-'0') * (str[2]-'0') * (str[3]-'0') * (str[4]-'0');
    int tmp = sum;
    for(int i = 5, j = 0; i < l; ++i, ++j) {
        if(str[i] == '0') {
            tmp = 0;
            i += 4;
            j += 4;
            continue;
        }
        if(tmp == 0) tmp = (str[j+1]-'0') * (str[j+2]-'0') * (str[j+3]-'0') * (str[j+4]-'0') * (str[j+5]-'0');
        else tmp = tmp / (str[j]-'0') * (str[i]-'0');
        if(tmp > sum) sum = tmp;
    }
    cout << sum << endl;
    return 0;
}