#include <stdio.h>#include <stdlib.h>#ifndef INT_MAX#define INT_MAX 0x7fffffff#endifstruct tree_node { int cnt, min;};struct seg_node { int a, b, s;};int N, M, E;struct tree_node tree[86432 * 4];struct seg_node in[10032];int cmp(const void *a, const void *b){ return ((struct seg_node *)a)->a - ((struct seg_node *)b)->a;}__inline int max(int a, int b){ return a > b ? a : b;}__inline int min(int a, int b){ return a < b ? a : b;}void tree_op(const int ins, int idx, int left, int right, int start, int end, int *val ){ int mid; if (ins) { if (!tree[idx].cnt || *val < tree[idx].min) tree[idx].min = *val; tree[idx].cnt++; } if (left == start && right == end) { if (!ins && tree[idx].cnt && tree[idx].min < *val) *val = tree[idx].min; return ; } mid = (left + right) / 2; if (end <= mid) tree_op(ins, idx*2, left, mid, start, end, val); else if (start > mid) tree_op(ins, idx*2 + 1, mid + 1, right, start, end, val); else { tree_op(ins, idx*2, left, mid, start, mid, val); tree_op(ins, idx*2 + 1, mid + 1, right, mid + 1, end, val); }}int main(){ int i, val, start, end; scanf("%d%d%d", &N, &M, &E); for (i = 0; i < N; i++) scanf("%d%d%d", &in[i].a, &in[i].b, &in[i].s); qsort(in, N, sizeof(in[0]), cmp); for (i = 0; i < N; i++) { if (in[i].b < M) continue; if (in[i].a > E) break; start = max(M, in[i].a - 1); end = min(E, in[i].b); if (in[i].a == M) { tree_op(1, 1, M, E, end, end, &in[i].s); continue; } val = INT_MAX; tree_op(0, 1, M, E, start, end, &val); if (val == INT_MAX) continue; val += in[i].s; tree_op(1, 1, M, E, end, end, &val); } val = INT_MAX; tree_op(0, 1, M, E, E, E, &val); printf("%dn", val == INT_MAX ? -1 : val); return 0;}
