diff options
Diffstat (limited to '2021/day21')
| -rwxr-xr-x | 2021/day21/day21 | bin | 0 -> 32136 bytes | |||
| -rw-r--r-- | 2021/day21/day21.cpp | 65 | ||||
| -rw-r--r-- | 2021/day21/makefile | 2 |
3 files changed, 67 insertions, 0 deletions
diff --git a/2021/day21/day21 b/2021/day21/day21 Binary files differnew file mode 100755 index 0000000..5fa0bb4 --- /dev/null +++ b/2021/day21/day21 diff --git a/2021/day21/day21.cpp b/2021/day21/day21.cpp new file mode 100644 index 0000000..b1b764c --- /dev/null +++ b/2021/day21/day21.cpp @@ -0,0 +1,65 @@ +#include <iostream> +#include <string> + +long long winp = 0, winq = 0; + +void stepseq (int p, int q, int sp, int sq, int turn, int roll, int die) { + if (turn == 0) { + if (roll < 3) { + stepseq((p+die)%10, q, sp, sq, turn, roll+1, die+1); + } else { + int score = p==0 ? sp+10 : sp+p; + if (score >= 1000) std::cout << "win sq*die: " << sq*(die-1) << std::endl; + else stepseq(p, q, score, sq, (turn+1)%2, 0, die); + } + } + if (turn == 1) { + if (roll < 3) { + stepseq(p, (q+die)%10, sp, sq, turn, roll+1, die+1); + } else { + int score = q==0 ? sq+10 : sq+q; + if (score >= 1000) std::cout << "win sp*die: " << sp*(die-1) << std::endl; + else stepseq(p, q, sp, score, (turn+1)%2, 0, die); + } + } +} + +void step (int p, int q, int sp, int sq, int turn, long mul) { + //std::cout << p<<" "<<q<< " "<<sp << " " <<sq << ",,,, "<<turn<<" "<<mul<<std::endl; + int incp = p==0 ? 10 : p; + int incq = q==0 ? 10 : q; + if (sp+incp >= 21) { winp += mul; return; } + if (sq+incq >= 21) { winq += mul; return; } + if (turn % 2 == 0) { + int score = sp+incp; + if (turn == 0) score = 0; + step((p+3)%10, q, score, sq, turn+1, mul*1); + step((p+4)%10, q, score, sq, turn+1, mul*3); + step((p+5)%10, q, score, sq, turn+1, mul*6); + step((p+6)%10, q, score, sq, turn+1, mul*7); + step((p+7)%10, q, score, sq, turn+1, mul*6); + step((p+8)%10, q, score, sq, turn+1, mul*3); + step((p+9)%10, q, score, sq, turn+1, mul*1); + } + if (turn % 2 == 1) { + int score = sq+incq; + if (turn == 1) score = 0; + step(p, (q+3)%10, sp, score, turn+1, mul*1); + step(p, (q+4)%10, sp, score, turn+1, mul*3); + step(p, (q+5)%10, sp, score, turn+1, mul*6); + step(p, (q+6)%10, sp, score, turn+1, mul*7); + step(p, (q+7)%10, sp, score, turn+1, mul*6); + step(p, (q+8)%10, sp, score, turn+1, mul*3); + step(p, (q+9)%10, sp, score, turn+1, mul*1); + } +} + +int main (int argc, char *argv[]) { + int p = std::stoi(std::string{ argv[1] }); + int q = std::stoi(std::string{ argv[2] }); + stepseq(p, q, 0, 0, 0, 0, 1); + step(p, q, 0, 0, 0, 1); + std::cout << "wins " << winp << " " << winq << std::endl; + + return 0; +} diff --git a/2021/day21/makefile b/2021/day21/makefile new file mode 100644 index 0000000..512e963 --- /dev/null +++ b/2021/day21/makefile @@ -0,0 +1,2 @@ +all day21: + g++ -std=c++20 day21.cpp -o day21 |