|
| 1 | +/* |
| 2 | + * Copyright (C) 2022, Saul Lawliet <october dot sunbathe at gmail dot com> |
| 3 | + * All rights reserved. |
| 4 | + * |
| 5 | + * 一看这是一个动态规划的问题, 分析后发现需要画一个二叉树的表格? |
| 6 | + * 头一次遇到这样的问题, 兴奋极了, 一顿操作下来 |
| 7 | + * 又是 Memory Limit Exceeded, 又是 Time Limit Exceeded 的 |
| 8 | + * |
| 9 | + * 下个文件再从头开始... |
| 10 | + */ |
| 11 | + |
| 12 | +#include "c/data-structures/array.h" |
| 13 | +#include "c/test.h" |
| 14 | + |
| 15 | +struct Cell{ |
| 16 | + int v; // value |
| 17 | + int p; // [p, q] |
| 18 | + int q; |
| 19 | +}; |
| 20 | + |
| 21 | +int maximumScore(int *nums, int numsSize, int *multipliers, int multipliersSize) { |
| 22 | + // 构建二叉树型表格 |
| 23 | + struct Cell **table = malloc(sizeof(struct Cell *) * multipliersSize); |
| 24 | + for (int i = 0; i < multipliersSize; i++) { |
| 25 | + table[i] = malloc(sizeof(struct Cell) * (2 << i)); |
| 26 | + } |
| 27 | + |
| 28 | + for (int i = 0; i < multipliersSize; i++) { |
| 29 | + for (int j = 0; j < 1 << i; j++) { |
| 30 | + struct Cell cell = i == 0 ? (struct Cell){0, 0, numsSize - 1} : table[i - 1][j]; |
| 31 | + table[i][2 * j] = (struct Cell){cell.v + nums[cell.p] * multipliers[i], cell.p + 1, cell.q}; |
| 32 | + table[i][2 * j + 1] = (struct Cell){cell.v + nums[cell.q] * multipliers[i], cell.p, cell.q - 1}; |
| 33 | + } |
| 34 | + } |
| 35 | + |
| 36 | + int max = INT32_MIN; |
| 37 | + for (int i = 0; i < 1 << multipliersSize; i++) { |
| 38 | + if (table[multipliersSize-1][i].v > max) { |
| 39 | + max = table[multipliersSize-1][i].v; |
| 40 | + } |
| 41 | + } |
| 42 | + |
| 43 | + for (int i = 0; i < multipliersSize; i++) { |
| 44 | + free(table[i]); |
| 45 | + } |
| 46 | + free(table); |
| 47 | + |
| 48 | + return max; |
| 49 | +} |
| 50 | + |
| 51 | +void test(int expect, const char *nums, const char *multipliers) { |
| 52 | + arrayEntry *e1 = arrayParse1D(nums, ARRAY_INT); |
| 53 | + arrayEntry *e2 = arrayParse1D(multipliers, ARRAY_INT); |
| 54 | + |
| 55 | + EXPECT_EQ_INT(expect, maximumScore(arrayValue(e1), arraySize(e1), arrayValue(e2), arraySize(e2))); |
| 56 | + |
| 57 | + arrayFree(e2); |
| 58 | + arrayFree(e1); |
| 59 | +} |
| 60 | + |
| 61 | +int main(void) { |
| 62 | + test(14, "[1,2,3]", "[3,2,1]"); |
| 63 | + test(102, "[-5,-3,-3,-2,7,1]", "[-10,-5,3,4,6]"); |
| 64 | + |
| 65 | + return testOutput(); |
| 66 | +} |
0 commit comments