Brush questions - Luogu -p1161 turn on the light

P1161 turn on the light -C Language

1、 subject

2、 The problem solving process

(1) for the first time Overtime #define LIGHT 20000// Maximum value of lamp
result ：

Code ：

// Luogu  P1161  turn on the light 
#include <stdio.h>
#define NUM 5000//n<=5000
#define LIGHT 20000// Maximum value of lamp 
int main() {
    
	int n;// Conduct n operations 
	int light[LIGHT] = {
     0 };// The initial value is off 0
	double a[NUM] = {
     0.0 };
	int t[NUM] = {
     1 };
	int k;// You need to press the number of the switch 
	int i,j;
	scanf_s("%d", &n);
	for (i = 0; i < n; i++) {
    
		scanf_s("%lf %d", &a[i], &t[i]);
		for (j = 1; j <= t[i]; j++) {
    // The number of the lamp is from 1 Start 
			k = (int)(a[i]*j);// Down to the whole 
			light[k] = (light[k] == 0) ? 1 : 0;// Switch the state of the lamp 
		}
	}
	i = 1;// Start from the first light 
	while (light[i] == 0) {
    // The status of the lamp is off 
		i++;
	}
	printf("%d",i);// The status of the light is on 

	return 0;
}

(2) The second time
result ：

Code ：

// Luogu  P1161  turn on the light 
#include <stdio.h>
#define NUM 5000//n<=5000
#define LIGHT 20000// Maximum value of lamp 
int main() {
    
	int n;// Conduct n operations 
	int light[LIGHT] = {
     0 };// The initial value is off 0
	double a[NUM] = {
     0.0 };
	int t[NUM] = {
     1 };
	int k;// You need to press the number of the switch 
	int i,j;
	scanf("%d", &n);
	for (i = 0; i < n; i++) {
    
		scanf("%lf %d", &a[i], &t[i]);
		for (j = 1; j <= t[i]; j++) {
    // The number of the lamp is from 1 Start 
			k = (int)(a[i]*j);// Down to the whole 
			light[k] = (light[k] == 0) ? 1 : 0;// Switch the state of the lamp 
		}
	}
	i = 1;// Start from the first light 
	while (light[i] == 0) {
    // The status of the lamp is off 
		i++;
	}
	printf("%d",i);// The status of the light is on 

	return 0;
}