1478: Metric Matrice
Time Limit: 1 Sec Memory Limit: 128 MB
Submit: 72 Solved: 37
SubmitStatusWeb Board
Description
nt j, determine if the distance matrix is "a metric" or not.
A distance matrix a[i][j] is a metric if and only if
1. a[i][i] = 0
2. a[i][j]> 0 if i != j
3. a[i][j] = a[j][i]
4. a[i][j] + a[j][k] >= a[i][k] i 1 j 1 k
Input
The first line of input gives a single integer, 1 ≤ N ≤ 5, the number of test cases. Then follow, for each test case,
* Line 1: One integer, N, the rows and number of columns, 2 <= N <= 30
* Line 2..N+1: N lines, each with N space-separated integers
(-32000 <=each integer <= 32000).
Output
Output for each test case , a single line with a single digit, which is the lowest digit of the possible facts on this list:
* 0: The matrix is a metric
* 1: The matrix is not a metric, it violates rule 1 above
* 2: The matrix is not a metric, it violates rule 2 above
* 3: The matrix is not a metric, it violates rule 3 above
* 4: The matrix is not a metric, it violates rule 4 above
Sample Input
2
4
0 1 2 3
1 0 1 2
2 1 0 1
3 2 1 0
2
0 3
2 0
Sample Output
0
3
HINT
Source
第五届河南省大学生程序设计竞赛
题解:这道题是说:给出一个矩阵,看是否是符合规则的。如果均满足下列四种规则,输出0.
如果不满足1输出1
如果不满足2输出2
如果不满足3输出3
如果不满足4输出4
代码:
#include <iostream> #include <algorithm> #include <cstdio> #include <cstring> using namespace std; const int maxx=1005; int a[105][105]; int n; int x1,x2,x3,x4; ///是否符合第一种 inline int f1() { x1=1; for(int i=0;i<n;i++) { if(a[i][i]!=0) { x1=0; return x1; } } return x1; } ///是否符合第二种 inline int f2() { x2=1; for(int i=0;i<n;i++) { for(int j=0;j<n;j++) { if(i!=j) { if(a[i][j]<=0) { x2=0; return x2; } } } } return x2; } ///是否符合第三种 inline int f3() { x3=1; for(int i=0;i<n;i++) { for(int j=0;j<n;j++) { if(a[i][j]!=a[j][i]) { x3=0; return x3; } } } return x3; } ///是否符合第四种 inline int f4() { x4=1; for(int i=0;i<n;i++) { for(int j=0;j<n;j++) { for(int k=0;k<n;k++) { if(i!=j&&i!=k&&j!=k) if(a[i][j]+a[j][k]<a[i][k]) { x4=0; return x4; } } } } return x4; } int main() { int t; scanf("%d",&t); while(t--) { scanf("%d",&n); for(int i=0;i<n;i++) { for(int j=0;j<n;j++) { scanf("%d",&a[i][j]); } } int a1=f1(); int a2=f2(); int a3=f3(); int a4=f4(); if(a1==1&&a2==1&&a3==1&&a4==1) printf("0\n"); else if(a1==0) printf("1\n"); else if(a2==0) printf("2\n"); else if(a3==0) printf("3\n"); else if(a4==0) printf("4\n"); } return 0; }