Submission #77492177

Source Code Expand

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#include <stdio.h>
#include <stdlib.h>
struct xy_s {
  int X, Y;
};
int cmp(const void* x, const void* y) {
  struct xy_s a = *(const struct xy_s*)x, b = *(const struct xy_s*)y;
  return (a.Y > b.Y) - (a.Y < b.Y);
}
int N;
struct xy_s XY[312345];
int main(void) {
  int i;
  int min, ans;
  if (scanf("%d", &N) != 1) return 1;
  for (i = 0; i < N; i++) {
    if (scanf("%d%d", &XY[i].X, &XY[i].Y) != 2) return 1;
  }
  qsort(XY, N, sizeof(*XY), cmp);
  min = XY[0].X;
  ans = 1;
  for (i = 1; i < N; i++) {
    if (XY[i].X <= min) {
      ans++;
      min = XY[i].X;
    }
  }
  printf("%d\n", ans);
  return 0;
}
/*
下から順に処理 → おｋ iff X がそこまでの最小値
*/
 
 
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#include <stdio.h>
#include <stdlib.h>

struct xy_s {
	int X, Y;
};

int cmp(const void* x, const void* y) {
	struct xy_s a = *(const struct xy_s*)x, b = *(const struct xy_s*)y;
	return (a.Y > b.Y) - (a.Y < b.Y);
}

int N;
struct xy_s XY[312345];

int main(void) {
	int i;
	int min, ans;
	if (scanf("%d", &N) != 1) return 1;
	for (i = 0; i < N; i++) {
		if (scanf("%d%d", &XY[i].X, &XY[i].Y) != 2) return 1;
	}
	qsort(XY, N, sizeof(*XY), cmp);
	min = XY[0].X;
	ans = 1;
	for (i = 1; i < N; i++) {
		if (XY[i].X <= min) {
			ans++;
			min = XY[i].X;
		}
	}
	printf("%d\n", ans);
	return 0;
}

/*

下から順に処理 → おｋ iff X がそこまでの最小値

*/

Submission Info

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