C語言完整解法：
#define MaxValue 1000001
int findCheapestPrice(int n, int** flights, int flightsSize, int* flightsColSize, int src, int dst, int K) {
/* 異常判斷 */
if (n < 1 || n > 100 || K < 0 || K > 10000) {
return -1;
}
/* 創建數組存放結果 */
int **dp = (int **)malloc(sizeof(int *) * n);
for (int i = 0; i < n; i++) {
dp[i] = (int *)malloc(sizeof(int) * (K + 1));
}
/* 初始化數組 */
for (int i = 0; i < n; i++) {
for (int j = 0; j < K + 1; j++) {
dp[i][j] = MaxValue;
}
}
/* 初始化src到src的航班 */
for (int k = 0; k <= K; k++) {
dp[src][k] = 0;
}
/* 初始化src直達的航班 */
for (int i = 0; i < flightsSize; i++) {
if (flights[i][0] == src) {
dp[flights[i][1]][0] = flights[i][2];
}
}
/* 動態規劃 */
for (int k = 1; k <= K; k++) {
for (int i = 0; i < flightsSize; i++) {
if (dp[flights[i][0]][k - 1] != MaxValue) {
dp[flights[i][1]][k] = dp[flights[i][1]][k] > (dp[flights[i][0]][k - 1] + flights[i][2]) ? (dp[flights[i][0]][k - 1] + flights[i][2]) : dp[flights[i][1]][k];
}
}
}
return dp[dst][K] == MaxValue ? -1 : dp[dst][K];
}